diff --git a/bitwarden_license/src/Commercial.Core/AdminConsole/Services/ProviderService.cs b/bitwarden_license/src/Commercial.Core/AdminConsole/Services/ProviderService.cs
index ad2d2d2aa1..3c75be756a 100644
--- a/bitwarden_license/src/Commercial.Core/AdminConsole/Services/ProviderService.cs
+++ b/bitwarden_license/src/Commercial.Core/AdminConsole/Services/ProviderService.cs
@@ -287,11 +287,10 @@ public class ProviderService : IProviderService
 
         foreach (var user in users)
         {
-            if (!keyedFilteredUsers.ContainsKey(user.Id))
+            if (!keyedFilteredUsers.TryGetValue(user.Id, out var providerUser))
             {
                 continue;
             }
-            var providerUser = keyedFilteredUsers[user.Id];
             try
             {
                 if (providerUser.Status != ProviderUserStatusType.Accepted || providerUser.ProviderId != providerId)
diff --git a/bitwarden_license/src/Scim/Program.cs b/bitwarden_license/src/Scim/Program.cs
index 5d7d505aac..92f12f59dd 100644
--- a/bitwarden_license/src/Scim/Program.cs
+++ b/bitwarden_license/src/Scim/Program.cs
@@ -16,8 +16,8 @@ public class Program
                     {
                         var context = e.Properties["SourceContext"].ToString();
 
-                        if (e.Properties.ContainsKey("RequestPath") &&
-                            !string.IsNullOrWhiteSpace(e.Properties["RequestPath"]?.ToString()) &&
+                        if (e.Properties.TryGetValue("RequestPath", out var requestPath) &&
+                            !string.IsNullOrWhiteSpace(requestPath?.ToString()) &&
                             (context.Contains(".Server.Kestrel") || context.Contains(".Core.IISHttpServer")))
                         {
                             return false;
diff --git a/bitwarden_license/src/Sso/Controllers/AccountController.cs b/bitwarden_license/src/Sso/Controllers/AccountController.cs
index f41d2d3c65..5c03ba0017 100644
--- a/bitwarden_license/src/Sso/Controllers/AccountController.cs
+++ b/bitwarden_license/src/Sso/Controllers/AccountController.cs
@@ -370,8 +370,8 @@ public class AccountController : Controller
         //  for the user identifier.
         static bool nameIdIsNotTransient(Claim c) => c.Type == ClaimTypes.NameIdentifier
             && (c.Properties == null
-            || !c.Properties.ContainsKey(SamlPropertyKeys.ClaimFormat)
-            || c.Properties[SamlPropertyKeys.ClaimFormat] != SamlNameIdFormats.Transient);
+            || !c.Properties.TryGetValue(SamlPropertyKeys.ClaimFormat, out var claimFormat)
+            || claimFormat != SamlNameIdFormats.Transient);
 
         // Try to determine the unique id of the external user (issued by the provider)
         // the most common claim type for that are the sub claim and the NameIdentifier
diff --git a/bitwarden_license/src/Sso/Program.cs b/bitwarden_license/src/Sso/Program.cs
index 051caca9c2..1a8ce6eb88 100644
--- a/bitwarden_license/src/Sso/Program.cs
+++ b/bitwarden_license/src/Sso/Program.cs
@@ -17,8 +17,8 @@ public class Program
                 logging.AddSerilog(hostingContext, (e, globalSettings) =>
                 {
                     var context = e.Properties["SourceContext"].ToString();
-                    if (e.Properties.ContainsKey("RequestPath") &&
-                        !string.IsNullOrWhiteSpace(e.Properties["RequestPath"]?.ToString()) &&
+                    if (e.Properties.TryGetValue("RequestPath", out var requestPath) &&
+                        !string.IsNullOrWhiteSpace(requestPath?.ToString()) &&
                         (context.Contains(".Server.Kestrel") || context.Contains(".Core.IISHttpServer")))
                     {
                         return false;
diff --git a/bitwarden_license/src/Sso/Utilities/OpenIdConnectOptionsExtensions.cs b/bitwarden_license/src/Sso/Utilities/OpenIdConnectOptionsExtensions.cs
index 9221877a04..825ed74dc8 100644
--- a/bitwarden_license/src/Sso/Utilities/OpenIdConnectOptionsExtensions.cs
+++ b/bitwarden_license/src/Sso/Utilities/OpenIdConnectOptionsExtensions.cs
@@ -46,9 +46,9 @@ public static class OpenIdConnectOptionsExtensions
 
             // Handle State if we've gotten that back
             var decodedState = options.StateDataFormat.Unprotect(state);
-            if (decodedState != null && decodedState.Items.ContainsKey("scheme"))
+            if (decodedState != null && decodedState.Items.TryGetValue("scheme", out var stateScheme))
             {
-                return decodedState.Items["scheme"] == scheme;
+                return stateScheme == scheme;
             }
         }
         catch
diff --git a/src/Admin/IdentityServer/ReadOnlyEnvIdentityUserStore.cs b/src/Admin/IdentityServer/ReadOnlyEnvIdentityUserStore.cs
index 15b8d894b7..89f04230b3 100644
--- a/src/Admin/IdentityServer/ReadOnlyEnvIdentityUserStore.cs
+++ b/src/Admin/IdentityServer/ReadOnlyEnvIdentityUserStore.cs
@@ -39,7 +39,7 @@ public class ReadOnlyEnvIdentityUserStore : ReadOnlyIdentityUserStore
             }
         }
 
-        var userStamp = usersDict.ContainsKey(normalizedEmail) ? usersDict[normalizedEmail] : null;
+        var userStamp = usersDict.GetValueOrDefault(normalizedEmail);
         if (userStamp == null)
         {
             return Task.FromResult<IdentityUser>(null);
diff --git a/src/Admin/Program.cs b/src/Admin/Program.cs
index fb5dc7e08b..05bf35d41d 100644
--- a/src/Admin/Program.cs
+++ b/src/Admin/Program.cs
@@ -20,8 +20,8 @@ public class Program
                 logging.AddSerilog(hostingContext, (e, globalSettings) =>
                 {
                     var context = e.Properties["SourceContext"].ToString();
-                    if (e.Properties.ContainsKey("RequestPath") &&
-                        !string.IsNullOrWhiteSpace(e.Properties["RequestPath"]?.ToString()) &&
+                    if (e.Properties.TryGetValue("RequestPath", out var requestPath) &&
+                        !string.IsNullOrWhiteSpace(requestPath?.ToString()) &&
                         (context.Contains(".Server.Kestrel") || context.Contains(".Core.IISHttpServer")))
                     {
                         return false;
diff --git a/src/Admin/Services/AccessControlService.cs b/src/Admin/Services/AccessControlService.cs
index f45f30e216..a2ba9fa6ff 100644
--- a/src/Admin/Services/AccessControlService.cs
+++ b/src/Admin/Services/AccessControlService.cs
@@ -29,12 +29,12 @@ public class AccessControlService : IAccessControlService
         }
 
         var userRole = GetUserRoleFromClaim();
-        if (string.IsNullOrEmpty(userRole) || !RolePermissionMapping.RolePermissions.ContainsKey(userRole))
+        if (string.IsNullOrEmpty(userRole) || !RolePermissionMapping.RolePermissions.TryGetValue(userRole, out var rolePermissions))
         {
             return false;
         }
 
-        return RolePermissionMapping.RolePermissions[userRole].Contains(permission);
+        return rolePermissions.Contains(permission);
     }
 
     public string GetUserRole(string userEmail)
diff --git a/src/Api/Auth/Models/Request/TwoFactorRequestModels.cs b/src/Api/Auth/Models/Request/TwoFactorRequestModels.cs
index 357db5ad1e..8d7df4160d 100644
--- a/src/Api/Auth/Models/Request/TwoFactorRequestModels.cs
+++ b/src/Api/Auth/Models/Request/TwoFactorRequestModels.cs
@@ -25,7 +25,7 @@ public class UpdateTwoFactorAuthenticatorRequestModel : SecretVerificationReques
         {
             providers = new Dictionary<TwoFactorProviderType, TwoFactorProvider>();
         }
-        else if (providers.ContainsKey(TwoFactorProviderType.Authenticator))
+        else
         {
             providers.Remove(TwoFactorProviderType.Authenticator);
         }
@@ -62,7 +62,7 @@ public class UpdateTwoFactorDuoRequestModel : SecretVerificationRequestModel, IV
         {
             providers = [];
         }
-        else if (providers.ContainsKey(TwoFactorProviderType.Duo))
+        else
         {
             providers.Remove(TwoFactorProviderType.Duo);
         }
@@ -88,7 +88,7 @@ public class UpdateTwoFactorDuoRequestModel : SecretVerificationRequestModel, IV
         {
             providers = [];
         }
-        else if (providers.ContainsKey(TwoFactorProviderType.OrganizationDuo))
+        else
         {
             providers.Remove(TwoFactorProviderType.OrganizationDuo);
         }
@@ -145,7 +145,7 @@ public class UpdateTwoFactorYubicoOtpRequestModel : SecretVerificationRequestMod
         {
             providers = new Dictionary<TwoFactorProviderType, TwoFactorProvider>();
         }
-        else if (providers.ContainsKey(TwoFactorProviderType.YubiKey))
+        else
         {
             providers.Remove(TwoFactorProviderType.YubiKey);
         }
@@ -228,7 +228,7 @@ public class TwoFactorEmailRequestModel : SecretVerificationRequestModel
         {
             providers = new Dictionary<TwoFactorProviderType, TwoFactorProvider>();
         }
-        else if (providers.ContainsKey(TwoFactorProviderType.Email))
+        else
         {
             providers.Remove(TwoFactorProviderType.Email);
         }
diff --git a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorAuthenticatorResponseModel.cs b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorAuthenticatorResponseModel.cs
index f791c6fb1e..71569174a7 100644
--- a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorAuthenticatorResponseModel.cs
+++ b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorAuthenticatorResponseModel.cs
@@ -13,9 +13,9 @@ public class TwoFactorAuthenticatorResponseModel : ResponseModel
         ArgumentNullException.ThrowIfNull(user);
 
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.Authenticator);
-        if (provider?.MetaData?.ContainsKey("Key") ?? false)
+        if (provider?.MetaData?.TryGetValue("Key", out var keyValue) ?? false)
         {
-            Key = (string)provider.MetaData["Key"];
+            Key = (string)keyValue;
             Enabled = provider.Enabled;
         }
         else
diff --git a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorEmailResponseModel.cs b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorEmailResponseModel.cs
index ee1797f83e..d1d87d85b5 100644
--- a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorEmailResponseModel.cs
+++ b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorEmailResponseModel.cs
@@ -15,9 +15,9 @@ public class TwoFactorEmailResponseModel : ResponseModel
         }
 
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.Email);
-        if (provider?.MetaData?.ContainsKey("Email") ?? false)
+        if (provider?.MetaData?.TryGetValue("Email", out var email) ?? false)
         {
-            Email = (string)provider.MetaData["Email"];
+            Email = (string)email;
             Enabled = provider.Enabled;
         }
         else
diff --git a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorYubiKeyResponseModel.cs b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorYubiKeyResponseModel.cs
index 014863497d..0a97367017 100644
--- a/src/Api/Auth/Models/Response/TwoFactor/TwoFactorYubiKeyResponseModel.cs
+++ b/src/Api/Auth/Models/Response/TwoFactor/TwoFactorYubiKeyResponseModel.cs
@@ -19,29 +19,29 @@ public class TwoFactorYubiKeyResponseModel : ResponseModel
         {
             Enabled = provider.Enabled;
 
-            if (provider.MetaData.ContainsKey("Key1"))
+            if (provider.MetaData.TryGetValue("Key1", out var key1))
             {
-                Key1 = (string)provider.MetaData["Key1"];
+                Key1 = (string)key1;
             }
-            if (provider.MetaData.ContainsKey("Key2"))
+            if (provider.MetaData.TryGetValue("Key2", out var key2))
             {
-                Key2 = (string)provider.MetaData["Key2"];
+                Key2 = (string)key2;
             }
-            if (provider.MetaData.ContainsKey("Key3"))
+            if (provider.MetaData.TryGetValue("Key3", out var key3))
             {
-                Key3 = (string)provider.MetaData["Key3"];
+                Key3 = (string)key3;
             }
-            if (provider.MetaData.ContainsKey("Key4"))
+            if (provider.MetaData.TryGetValue("Key4", out var key4))
             {
-                Key4 = (string)provider.MetaData["Key4"];
+                Key4 = (string)key4;
             }
-            if (provider.MetaData.ContainsKey("Key5"))
+            if (provider.MetaData.TryGetValue("Key5", out var key5))
             {
-                Key5 = (string)provider.MetaData["Key5"];
+                Key5 = (string)key5;
             }
-            if (provider.MetaData.ContainsKey("Nfc"))
+            if (provider.MetaData.TryGetValue("Nfc", out var nfc))
             {
-                Nfc = (bool)provider.MetaData["Nfc"];
+                Nfc = (bool)nfc;
             }
         }
         else
diff --git a/src/Api/Utilities/ApiHelpers.cs b/src/Api/Utilities/ApiHelpers.cs
index f4f1830e16..2c6dc8b73b 100644
--- a/src/Api/Utilities/ApiHelpers.cs
+++ b/src/Api/Utilities/ApiHelpers.cs
@@ -62,9 +62,9 @@ public static class ApiHelpers
                 }
             }
 
-            if (eventTypeHandlers.ContainsKey(eventGridEvent.EventType))
+            if (eventTypeHandlers.TryGetValue(eventGridEvent.EventType, out var eventTypeHandler))
             {
-                await eventTypeHandlers[eventGridEvent.EventType](eventGridEvent);
+                await eventTypeHandler(eventGridEvent);
             }
         }
 
diff --git a/src/Api/Vault/Controllers/CiphersController.cs b/src/Api/Vault/Controllers/CiphersController.cs
index d603c75505..92b611f588 100644
--- a/src/Api/Vault/Controllers/CiphersController.cs
+++ b/src/Api/Vault/Controllers/CiphersController.cs
@@ -1188,14 +1188,14 @@ public class CiphersController : Controller
         var cipher = await GetByIdAsync(id, userId);
         var attachments = cipher?.GetAttachments();
 
-        if (attachments == null || !attachments.ContainsKey(attachmentId) || attachments[attachmentId].Validated)
+        if (attachments == null || !attachments.TryGetValue(attachmentId, out var attachment) || attachment.Validated)
         {
             throw new NotFoundException();
         }
 
         return new AttachmentUploadDataResponseModel
         {
-            Url = await _attachmentStorageService.GetAttachmentUploadUrlAsync(cipher, attachments[attachmentId]),
+            Url = await _attachmentStorageService.GetAttachmentUploadUrlAsync(cipher, attachment),
             FileUploadType = _attachmentStorageService.FileUploadType,
         };
     }
@@ -1214,11 +1214,10 @@ public class CiphersController : Controller
         var userId = _userService.GetProperUserId(User).Value;
         var cipher = await GetByIdAsync(id, userId);
         var attachments = cipher?.GetAttachments();
-        if (attachments == null || !attachments.ContainsKey(attachmentId))
+        if (attachments == null || !attachments.TryGetValue(attachmentId, out var attachmentData))
         {
             throw new NotFoundException();
         }
-        var attachmentData = attachments[attachmentId];
 
         await Request.GetFileAsync(async (stream) =>
         {
@@ -1368,7 +1367,7 @@ public class CiphersController : Controller
                         var cipher = await _cipherRepository.GetByIdAsync(new Guid(cipherId));
                         var attachments = cipher?.GetAttachments() ?? new Dictionary<string, CipherAttachment.MetaData>();
 
-                        if (cipher == null || !attachments.ContainsKey(attachmentId) || attachments[attachmentId].Validated)
+                        if (cipher == null || !attachments.TryGetValue(attachmentId, out var attachment) || attachment.Validated)
                         {
                             if (_attachmentStorageService is AzureSendFileStorageService azureFileStorageService)
                             {
@@ -1378,7 +1377,7 @@ public class CiphersController : Controller
                             return;
                         }
 
-                        await _cipherService.ValidateCipherAttachmentFile(cipher, attachments[attachmentId]);
+                        await _cipherService.ValidateCipherAttachmentFile(cipher, attachment);
                     }
                     catch (Exception e)
                     {
diff --git a/src/Api/Vault/Models/Request/CipherRequestModel.cs b/src/Api/Vault/Models/Request/CipherRequestModel.cs
index 5c288ab66d..229d27e484 100644
--- a/src/Api/Vault/Models/Request/CipherRequestModel.cs
+++ b/src/Api/Vault/Models/Request/CipherRequestModel.cs
@@ -113,18 +113,25 @@ public class CipherRequestModel
 
         if (hasAttachments2)
         {
-            foreach (var attachment in attachments.Where(a => Attachments2.ContainsKey(a.Key)))
+            foreach (var attachment in attachments)
             {
-                var attachment2 = Attachments2[attachment.Key];
+                if (!Attachments2.TryGetValue(attachment.Key, out var attachment2))
+                {
+                    continue;
+                }
                 attachment.Value.FileName = attachment2.FileName;
                 attachment.Value.Key = attachment2.Key;
             }
         }
         else if (hasAttachments)
         {
-            foreach (var attachment in attachments.Where(a => Attachments.ContainsKey(a.Key)))
+            foreach (var attachment in attachments)
             {
-                attachment.Value.FileName = Attachments[attachment.Key];
+                if (!Attachments.TryGetValue(attachment.Key, out var attachmentForKey))
+                {
+                    continue;
+                }
+                attachment.Value.FileName = attachmentForKey;
                 attachment.Value.Key = null;
             }
         }
diff --git a/src/Api/Vault/Models/Response/CipherResponseModel.cs b/src/Api/Vault/Models/Response/CipherResponseModel.cs
index 358da3e62a..240783837e 100644
--- a/src/Api/Vault/Models/Response/CipherResponseModel.cs
+++ b/src/Api/Vault/Models/Response/CipherResponseModel.cs
@@ -129,13 +129,13 @@ public class CipherDetailsResponseModel : CipherResponseModel
         IDictionary<Guid, IGrouping<Guid, CollectionCipher>> collectionCiphers, string obj = "cipherDetails")
         : base(cipher, user, organizationAbilities, globalSettings, obj)
     {
-        if (collectionCiphers?.ContainsKey(cipher.Id) ?? false)
+        if (collectionCiphers?.TryGetValue(cipher.Id, out var collectionCipher) ?? false)
         {
-            CollectionIds = collectionCiphers[cipher.Id].Select(c => c.CollectionId);
+            CollectionIds = collectionCipher.Select(c => c.CollectionId);
         }
         else
         {
-            CollectionIds = new Guid[] { };
+            CollectionIds = [];
         }
     }
 
@@ -147,7 +147,7 @@ public class CipherDetailsResponseModel : CipherResponseModel
         IEnumerable<CollectionCipher> collectionCiphers, string obj = "cipherDetails")
         : base(cipher, user, organizationAbilities, globalSettings, obj)
     {
-        CollectionIds = collectionCiphers?.Select(c => c.CollectionId) ?? new List<Guid>();
+        CollectionIds = collectionCiphers?.Select(c => c.CollectionId) ?? [];
     }
 
     public CipherDetailsResponseModel(
@@ -158,7 +158,7 @@ public class CipherDetailsResponseModel : CipherResponseModel
         string obj = "cipherDetails")
         : base(cipher, user, organizationAbilities, globalSettings, obj)
     {
-        CollectionIds = cipher.CollectionIds ?? new List<Guid>();
+        CollectionIds = cipher.CollectionIds ?? [];
     }
 
     public IEnumerable<Guid> CollectionIds { get; set; }
@@ -170,13 +170,13 @@ public class CipherMiniDetailsResponseModel : CipherMiniResponseModel
         IDictionary<Guid, IGrouping<Guid, CollectionCipher>> collectionCiphers, bool orgUseTotp, string obj = "cipherMiniDetails")
         : base(cipher, globalSettings, orgUseTotp, obj)
     {
-        if (collectionCiphers?.ContainsKey(cipher.Id) ?? false)
+        if (collectionCiphers?.TryGetValue(cipher.Id, out var collectionCipher) ?? false)
         {
-            CollectionIds = collectionCiphers[cipher.Id].Select(c => c.CollectionId);
+            CollectionIds = collectionCipher.Select(c => c.CollectionId);
         }
         else
         {
-            CollectionIds = new Guid[] { };
+            CollectionIds = [];
         }
     }
 
@@ -184,7 +184,7 @@ public class CipherMiniDetailsResponseModel : CipherMiniResponseModel
         GlobalSettings globalSettings, bool orgUseTotp, string obj = "cipherMiniDetails")
         : base(cipher, globalSettings, orgUseTotp, obj)
     {
-        CollectionIds = cipher.CollectionIds ?? new List<Guid>();
+        CollectionIds = cipher.CollectionIds ?? [];
     }
 
     public CipherMiniDetailsResponseModel(CipherOrganizationDetailsWithCollections cipher,
diff --git a/src/Billing/Controllers/AppleController.cs b/src/Billing/Controllers/AppleController.cs
index 1bcbbf2ad6..5c231de8ed 100644
--- a/src/Billing/Controllers/AppleController.cs
+++ b/src/Billing/Controllers/AppleController.cs
@@ -28,8 +28,8 @@ public class AppleController : Controller
             return new BadRequestResult();
         }
 
-        var key = HttpContext.Request.Query.ContainsKey("key") ?
-            HttpContext.Request.Query["key"].ToString() : null;
+        var key = HttpContext.Request.Query.TryGetValue("key", out var keyValue) ?
+            keyValue.ToString() : null;
         if (!CoreHelpers.FixedTimeEquals(key, _billingSettings.AppleWebhookKey))
         {
             return new BadRequestResult();
diff --git a/src/Billing/Controllers/PayPalController.cs b/src/Billing/Controllers/PayPalController.cs
index 2afde80601..36987c6e44 100644
--- a/src/Billing/Controllers/PayPalController.cs
+++ b/src/Billing/Controllers/PayPalController.cs
@@ -51,8 +51,8 @@ public class PayPalController : Controller
     [HttpPost("ipn")]
     public async Task<IActionResult> PostIpn()
     {
-        var key = HttpContext.Request.Query.ContainsKey("key")
-            ? HttpContext.Request.Query["key"].ToString()
+        var key = HttpContext.Request.Query.TryGetValue("key", out var keyValue)
+            ? keyValue.ToString()
             : null;
 
         if (string.IsNullOrEmpty(key))
diff --git a/src/Billing/Program.cs b/src/Billing/Program.cs
index 33e2665427..3e005ce7fd 100644
--- a/src/Billing/Program.cs
+++ b/src/Billing/Program.cs
@@ -20,8 +20,8 @@ public class Program
                             return e.Level >= globalSettings.MinLogLevel.BillingSettings.Jobs;
                         }
 
-                        if (e.Properties.ContainsKey("RequestPath") &&
-                            !string.IsNullOrWhiteSpace(e.Properties["RequestPath"]?.ToString()) &&
+                        if (e.Properties.TryGetValue("RequestPath", out var requestPath) &&
+                            !string.IsNullOrWhiteSpace(requestPath?.ToString()) &&
                             (context.Contains(".Server.Kestrel") || context.Contains(".Core.IISHttpServer")))
                         {
                             return false;
diff --git a/src/Core/AdminConsole/Entities/Organization.cs b/src/Core/AdminConsole/Entities/Organization.cs
index ee01414eb4..274c7f8ddb 100644
--- a/src/Core/AdminConsole/Entities/Organization.cs
+++ b/src/Core/AdminConsole/Entities/Organization.cs
@@ -257,12 +257,12 @@ public class Organization : ITableObject<Guid>, IStorableSubscriber, IRevisable
     public bool TwoFactorProviderIsEnabled(TwoFactorProviderType provider)
     {
         var providers = GetTwoFactorProviders();
-        if (providers == null || !providers.ContainsKey(provider))
+        if (providers == null || !providers.TryGetValue(provider, out var twoFactorProvider))
         {
             return false;
         }
 
-        return providers[provider].Enabled && Use2fa;
+        return twoFactorProvider.Enabled && Use2fa;
     }
 
     public bool TwoFactorIsEnabled()
@@ -279,12 +279,7 @@ public class Organization : ITableObject<Guid>, IStorableSubscriber, IRevisable
     public TwoFactorProvider? GetTwoFactorProvider(TwoFactorProviderType provider)
     {
         var providers = GetTwoFactorProviders();
-        if (providers == null || !providers.ContainsKey(provider))
-        {
-            return null;
-        }
-
-        return providers[provider];
+        return providers?.GetValueOrDefault(provider);
     }
 
     public void UpdateFromLicense(OrganizationLicense license, IFeatureService featureService)
diff --git a/src/Core/AdminConsole/OrganizationFeatures/Policies/Implementations/SavePolicyCommand.cs b/src/Core/AdminConsole/OrganizationFeatures/Policies/Implementations/SavePolicyCommand.cs
index cf332e689a..71212aaf4c 100644
--- a/src/Core/AdminConsole/OrganizationFeatures/Policies/Implementations/SavePolicyCommand.cs
+++ b/src/Core/AdminConsole/OrganizationFeatures/Policies/Implementations/SavePolicyCommand.cs
@@ -104,8 +104,8 @@ public class SavePolicyCommand : ISavePolicyCommand
             var dependentPolicyTypes = _policyValidators.Values
                 .Where(otherValidator => otherValidator.RequiredPolicies.Contains(policyUpdate.Type))
                 .Select(otherValidator => otherValidator.Type)
-                .Where(otherPolicyType => savedPoliciesDict.ContainsKey(otherPolicyType) &&
-                    savedPoliciesDict[otherPolicyType].Enabled)
+                .Where(otherPolicyType => savedPoliciesDict.TryGetValue(otherPolicyType, out var savedPolicy) &&
+                                          savedPolicy.Enabled)
                 .ToList();
 
             switch (dependentPolicyTypes)
diff --git a/src/Core/AdminConsole/Services/Implementations/EventService.cs b/src/Core/AdminConsole/Services/Implementations/EventService.cs
index 0cecda61a7..88d9595b4a 100644
--- a/src/Core/AdminConsole/Services/Implementations/EventService.cs
+++ b/src/Core/AdminConsole/Services/Implementations/EventService.cs
@@ -462,13 +462,13 @@ public class EventService : IEventService
 
     private bool CanUseEvents(IDictionary<Guid, OrganizationAbility> orgAbilities, Guid orgId)
     {
-        return orgAbilities != null && orgAbilities.ContainsKey(orgId) &&
-               orgAbilities[orgId].Enabled && orgAbilities[orgId].UseEvents;
+        return orgAbilities != null && orgAbilities.TryGetValue(orgId, out var orgAbility) &&
+               orgAbility.Enabled && orgAbility.UseEvents;
     }
 
     private bool CanUseProviderEvents(IDictionary<Guid, ProviderAbility> providerAbilities, Guid providerId)
     {
-        return providerAbilities != null && providerAbilities.ContainsKey(providerId) &&
-               providerAbilities[providerId].Enabled && providerAbilities[providerId].UseEvents;
+        return providerAbilities != null && providerAbilities.TryGetValue(providerId, out var providerAbility) &&
+               providerAbility.Enabled && providerAbility.UseEvents;
     }
 }
diff --git a/src/Core/AdminConsole/Services/Implementations/OrganizationService.cs b/src/Core/AdminConsole/Services/Implementations/OrganizationService.cs
index cbf2ae9d73..16e58d27ad 100644
--- a/src/Core/AdminConsole/Services/Implementations/OrganizationService.cs
+++ b/src/Core/AdminConsole/Services/Implementations/OrganizationService.cs
@@ -612,12 +612,12 @@ public class OrganizationService : IOrganizationService
         }
 
         var providers = organization.GetTwoFactorProviders();
-        if (!providers?.ContainsKey(type) ?? true)
+        if (providers is null || !providers.TryGetValue(type, out var provider))
         {
             return;
         }
 
-        providers[type].Enabled = true;
+        provider.Enabled = true;
         organization.SetTwoFactorProviders(providers);
         await UpdateAsync(organization);
     }
@@ -1115,7 +1115,7 @@ public class OrganizationService : IOrganizationService
             var existingUsersDict = existingExternalUsers.ToDictionary(u => u.ExternalId);
             var removeUsersSet = new HashSet<string>(removeUserExternalIds)
                 .Except(newUsersSet)
-                .Where(u => existingUsersDict.ContainsKey(u) && existingUsersDict[u].Type != OrganizationUserType.Owner)
+                .Where(u => existingUsersDict.TryGetValue(u, out var existingUser) && existingUser.Type != OrganizationUserType.Owner)
                 .Select(u => existingUsersDict[u]);
 
             await _organizationUserRepository.DeleteManyAsync(removeUsersSet.Select(u => u.Id));
diff --git a/src/Core/AdminConsole/Services/Implementations/PolicyService.cs b/src/Core/AdminConsole/Services/Implementations/PolicyService.cs
index c3eb2272d0..d424bd8fff 100644
--- a/src/Core/AdminConsole/Services/Implementations/PolicyService.cs
+++ b/src/Core/AdminConsole/Services/Implementations/PolicyService.cs
@@ -68,7 +68,7 @@ public class PolicyService : IPolicyService
         var excludedUserTypes = GetUserTypesExcludedFromPolicy(policyType);
         var orgAbilities = await _applicationCacheService.GetOrganizationAbilitiesAsync();
         return organizationUserPolicyDetails.Where(o =>
-            (!orgAbilities.ContainsKey(o.OrganizationId) || orgAbilities[o.OrganizationId].UsePolicies) &&
+            (!orgAbilities.TryGetValue(o.OrganizationId, out var orgAbility) || orgAbility.UsePolicies) &&
             o.PolicyEnabled &&
             !excludedUserTypes.Contains(o.OrganizationUserType) &&
             o.OrganizationUserStatus >= minStatus &&
diff --git a/src/Core/Auth/Identity/TokenProviders/EmailTwoFactorTokenProvider.cs b/src/Core/Auth/Identity/TokenProviders/EmailTwoFactorTokenProvider.cs
index 718e44ae5f..2f8481cea2 100644
--- a/src/Core/Auth/Identity/TokenProviders/EmailTwoFactorTokenProvider.cs
+++ b/src/Core/Auth/Identity/TokenProviders/EmailTwoFactorTokenProvider.cs
@@ -43,7 +43,7 @@ public class EmailTwoFactorTokenProvider : EmailTokenProvider
 
     private static bool HasProperMetaData(TwoFactorProvider provider)
     {
-        return provider?.MetaData != null && provider.MetaData.ContainsKey("Email") &&
-            !string.IsNullOrWhiteSpace((string)provider.MetaData["Email"]);
+        return provider?.MetaData != null && provider.MetaData.TryGetValue("Email", out var emailValue) &&
+            !string.IsNullOrWhiteSpace((string)emailValue);
     }
 }
diff --git a/src/Core/Auth/Identity/TokenProviders/WebAuthnTokenProvider.cs b/src/Core/Auth/Identity/TokenProviders/WebAuthnTokenProvider.cs
index 0bf75d0fc3..3b4b0fa520 100644
--- a/src/Core/Auth/Identity/TokenProviders/WebAuthnTokenProvider.cs
+++ b/src/Core/Auth/Identity/TokenProviders/WebAuthnTokenProvider.cs
@@ -80,7 +80,7 @@ public class WebAuthnTokenProvider : IUserTwoFactorTokenProvider<User>
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.WebAuthn);
         var keys = LoadKeys(provider);
 
-        if (!provider.MetaData.TryGetValue("login", out var value))
+        if (!provider.MetaData.TryGetValue("login", out var login))
         {
             return false;
         }
@@ -88,7 +88,7 @@ public class WebAuthnTokenProvider : IUserTwoFactorTokenProvider<User>
         var clientResponse = JsonSerializer.Deserialize<AuthenticatorAssertionRawResponse>(token,
             new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
 
-        var jsonOptions = value.ToString();
+        var jsonOptions = login.ToString();
         var options = AssertionOptions.FromJson(jsonOptions);
 
         var webAuthCred = keys.Find(k => k.Item2.Descriptor.Id.SequenceEqual(clientResponse.Id));
@@ -148,9 +148,9 @@ public class WebAuthnTokenProvider : IUserTwoFactorTokenProvider<User>
         for (var i = 1; i <= 5; i++)
         {
             var keyName = $"Key{i}";
-            if (provider.MetaData.ContainsKey(keyName))
+            if (provider.MetaData.TryGetValue(keyName, out var value))
             {
-                var key = new TwoFactorProvider.WebAuthnData((dynamic)provider.MetaData[keyName]);
+                var key = new TwoFactorProvider.WebAuthnData((dynamic)value);
 
                 keys.Add(new Tuple<string, TwoFactorProvider.WebAuthnData>(keyName, key));
             }
diff --git a/src/Core/Context/CurrentContext.cs b/src/Core/Context/CurrentContext.cs
index cbd90055b0..68d4606907 100644
--- a/src/Core/Context/CurrentContext.cs
+++ b/src/Core/Context/CurrentContext.cs
@@ -64,39 +64,39 @@ public class CurrentContext : ICurrentContext
         HttpContext = httpContext;
         await BuildAsync(httpContext.User, globalSettings);
 
-        if (DeviceIdentifier == null && httpContext.Request.Headers.ContainsKey("Device-Identifier"))
+        if (DeviceIdentifier == null && httpContext.Request.Headers.TryGetValue("Device-Identifier", out var deviceIdentifier))
         {
-            DeviceIdentifier = httpContext.Request.Headers["Device-Identifier"];
+            DeviceIdentifier = deviceIdentifier;
         }
 
-        if (httpContext.Request.Headers.ContainsKey("Device-Type") &&
-            Enum.TryParse(httpContext.Request.Headers["Device-Type"].ToString(), out DeviceType dType))
+        if (httpContext.Request.Headers.TryGetValue("Device-Type", out var deviceType) &&
+            Enum.TryParse(deviceType.ToString(), out DeviceType dType))
         {
             DeviceType = dType;
         }
 
-        if (!BotScore.HasValue && httpContext.Request.Headers.ContainsKey("X-Cf-Bot-Score") &&
-            int.TryParse(httpContext.Request.Headers["X-Cf-Bot-Score"], out var parsedBotScore))
+        if (!BotScore.HasValue && httpContext.Request.Headers.TryGetValue("X-Cf-Bot-Score", out var cfBotScore) &&
+            int.TryParse(cfBotScore, out var parsedBotScore))
         {
             BotScore = parsedBotScore;
         }
 
-        if (httpContext.Request.Headers.ContainsKey("X-Cf-Worked-Proxied"))
+        if (httpContext.Request.Headers.TryGetValue("X-Cf-Worked-Proxied", out var cfWorkedProxied))
         {
-            CloudflareWorkerProxied = httpContext.Request.Headers["X-Cf-Worked-Proxied"] == "1";
+            CloudflareWorkerProxied = cfWorkedProxied == "1";
         }
 
-        if (httpContext.Request.Headers.ContainsKey("X-Cf-Is-Bot"))
+        if (httpContext.Request.Headers.TryGetValue("X-Cf-Is-Bot", out var cfIsBot))
         {
-            IsBot = httpContext.Request.Headers["X-Cf-Is-Bot"] == "1";
+            IsBot = cfIsBot == "1";
         }
 
-        if (httpContext.Request.Headers.ContainsKey("X-Cf-Maybe-Bot"))
+        if (httpContext.Request.Headers.TryGetValue("X-Cf-Maybe-Bot", out var cfMaybeBot))
         {
-            MaybeBot = httpContext.Request.Headers["X-Cf-Maybe-Bot"] == "1";
+            MaybeBot = cfMaybeBot == "1";
         }
 
-        if (httpContext.Request.Headers.ContainsKey("Bitwarden-Client-Version") && Version.TryParse(httpContext.Request.Headers["Bitwarden-Client-Version"], out var cVersion))
+        if (httpContext.Request.Headers.TryGetValue("Bitwarden-Client-Version", out var bitWardenClientVersion) && Version.TryParse(bitWardenClientVersion, out var cVersion))
         {
             ClientVersion = cVersion;
         }
@@ -190,14 +190,14 @@ public class CurrentContext : ICurrentContext
 
     private List<CurrentContextOrganization> GetOrganizations(Dictionary<string, IEnumerable<Claim>> claimsDict, bool orgApi)
     {
-        var accessSecretsManager = claimsDict.ContainsKey(Claims.SecretsManagerAccess)
-            ? claimsDict[Claims.SecretsManagerAccess].ToDictionary(s => s.Value, _ => true)
+        var accessSecretsManager = claimsDict.TryGetValue(Claims.SecretsManagerAccess, out var secretsManagerAccessClaim)
+            ? secretsManagerAccessClaim.ToDictionary(s => s.Value, _ => true)
             : new Dictionary<string, bool>();
 
         var organizations = new List<CurrentContextOrganization>();
-        if (claimsDict.ContainsKey(Claims.OrganizationOwner))
+        if (claimsDict.TryGetValue(Claims.OrganizationOwner, out var organizationOwnerClaim))
         {
-            organizations.AddRange(claimsDict[Claims.OrganizationOwner].Select(c =>
+            organizations.AddRange(organizationOwnerClaim.Select(c =>
                 new CurrentContextOrganization
                 {
                     Id = new Guid(c.Value),
@@ -214,9 +214,9 @@ public class CurrentContext : ICurrentContext
             });
         }
 
-        if (claimsDict.ContainsKey(Claims.OrganizationAdmin))
+        if (claimsDict.TryGetValue(Claims.OrganizationAdmin, out var organizationAdminClaim))
         {
-            organizations.AddRange(claimsDict[Claims.OrganizationAdmin].Select(c =>
+            organizations.AddRange(organizationAdminClaim.Select(c =>
                 new CurrentContextOrganization
                 {
                     Id = new Guid(c.Value),
@@ -225,9 +225,9 @@ public class CurrentContext : ICurrentContext
                 }));
         }
 
-        if (claimsDict.ContainsKey(Claims.OrganizationUser))
+        if (claimsDict.TryGetValue(Claims.OrganizationUser, out var organizationUserClaim))
         {
-            organizations.AddRange(claimsDict[Claims.OrganizationUser].Select(c =>
+            organizations.AddRange(organizationUserClaim.Select(c =>
                 new CurrentContextOrganization
                 {
                     Id = new Guid(c.Value),
@@ -236,9 +236,9 @@ public class CurrentContext : ICurrentContext
                 }));
         }
 
-        if (claimsDict.ContainsKey(Claims.OrganizationCustom))
+        if (claimsDict.TryGetValue(Claims.OrganizationCustom, out var organizationCustomClaim))
         {
-            organizations.AddRange(claimsDict[Claims.OrganizationCustom].Select(c =>
+            organizations.AddRange(organizationCustomClaim.Select(c =>
                 new CurrentContextOrganization
                 {
                     Id = new Guid(c.Value),
@@ -254,9 +254,9 @@ public class CurrentContext : ICurrentContext
     private List<CurrentContextProvider> GetProviders(Dictionary<string, IEnumerable<Claim>> claimsDict)
     {
         var providers = new List<CurrentContextProvider>();
-        if (claimsDict.ContainsKey(Claims.ProviderAdmin))
+        if (claimsDict.TryGetValue(Claims.ProviderAdmin, out var providerAdminClaim))
         {
-            providers.AddRange(claimsDict[Claims.ProviderAdmin].Select(c =>
+            providers.AddRange(providerAdminClaim.Select(c =>
                 new CurrentContextProvider
                 {
                     Id = new Guid(c.Value),
@@ -264,9 +264,9 @@ public class CurrentContext : ICurrentContext
                 }));
         }
 
-        if (claimsDict.ContainsKey(Claims.ProviderServiceUser))
+        if (claimsDict.TryGetValue(Claims.ProviderServiceUser, out var providerServiceUserClaim))
         {
-            providers.AddRange(claimsDict[Claims.ProviderServiceUser].Select(c =>
+            providers.AddRange(providerServiceUserClaim.Select(c =>
                 new CurrentContextProvider
                 {
                     Id = new Guid(c.Value),
@@ -504,20 +504,20 @@ public class CurrentContext : ICurrentContext
 
     private string GetClaimValue(Dictionary<string, IEnumerable<Claim>> claims, string type)
     {
-        if (!claims.ContainsKey(type))
+        if (!claims.TryGetValue(type, out var claim))
         {
             return null;
         }
 
-        return claims[type].FirstOrDefault()?.Value;
+        return claim.FirstOrDefault()?.Value;
     }
 
     private Permissions SetOrganizationPermissionsFromClaims(string organizationId, Dictionary<string, IEnumerable<Claim>> claimsDict)
     {
         bool hasClaim(string claimKey)
         {
-            return claimsDict.ContainsKey(claimKey) ?
-                claimsDict[claimKey].Any(x => x.Value == organizationId) : false;
+            return claimsDict.TryGetValue(claimKey, out var claim) ?
+                claim.Any(x => x.Value == organizationId) : false;
         }
 
         return new Permissions
diff --git a/src/Core/Entities/User.cs b/src/Core/Entities/User.cs
index f3c54f0301..b92d22b0e3 100644
--- a/src/Core/Entities/User.cs
+++ b/src/Core/Entities/User.cs
@@ -195,12 +195,7 @@ public class User : ITableObject<Guid>, IStorableSubscriber, IRevisable, ITwoFac
     public TwoFactorProvider? GetTwoFactorProvider(TwoFactorProviderType provider)
     {
         var providers = GetTwoFactorProviders();
-        if (providers == null || !providers.TryGetValue(provider, out var value))
-        {
-            return null;
-        }
-
-        return value;
+        return providers?.GetValueOrDefault(provider);
     }
 
     public long StorageBytesRemaining()
diff --git a/src/Core/IdentityServer/DistributedCacheCookieManager.cs b/src/Core/IdentityServer/DistributedCacheCookieManager.cs
index 9771b40662..5d6717ac41 100644
--- a/src/Core/IdentityServer/DistributedCacheCookieManager.cs
+++ b/src/Core/IdentityServer/DistributedCacheCookieManager.cs
@@ -63,6 +63,6 @@ public class DistributedCacheCookieManager : ICookieManager
     private string GetKey(string key, string id) => $"{CacheKeyPrefix}-{key}-{id}";
 
     private string GetId(HttpContext context, string key) =>
-        context.Request.Cookies.ContainsKey(key) ?
-        context.Request.Cookies[key] : null;
+        context.Request.Cookies.TryGetValue(key, out var cookie) ?
+        cookie : null;
 }
diff --git a/src/Core/Services/Implementations/InMemoryApplicationCacheService.cs b/src/Core/Services/Implementations/InMemoryApplicationCacheService.cs
index 436e354954..0fde6d8906 100644
--- a/src/Core/Services/Implementations/InMemoryApplicationCacheService.cs
+++ b/src/Core/Services/Implementations/InMemoryApplicationCacheService.cs
@@ -50,14 +50,7 @@ public class InMemoryApplicationCacheService : IApplicationCacheService
         await InitProviderAbilitiesAsync();
         var newAbility = new ProviderAbility(provider);
 
-        if (_providerAbilities.ContainsKey(provider.Id))
-        {
-            _providerAbilities[provider.Id] = newAbility;
-        }
-        else
-        {
-            _providerAbilities.Add(provider.Id, newAbility);
-        }
+        _providerAbilities[provider.Id] = newAbility;
     }
 
     public virtual async Task UpsertOrganizationAbilityAsync(Organization organization)
@@ -65,32 +58,19 @@ public class InMemoryApplicationCacheService : IApplicationCacheService
         await InitOrganizationAbilitiesAsync();
         var newAbility = new OrganizationAbility(organization);
 
-        if (_orgAbilities.ContainsKey(organization.Id))
-        {
-            _orgAbilities[organization.Id] = newAbility;
-        }
-        else
-        {
-            _orgAbilities.Add(organization.Id, newAbility);
-        }
+        _orgAbilities[organization.Id] = newAbility;
     }
 
     public virtual Task DeleteOrganizationAbilityAsync(Guid organizationId)
     {
-        if (_orgAbilities != null && _orgAbilities.ContainsKey(organizationId))
-        {
-            _orgAbilities.Remove(organizationId);
-        }
+        _orgAbilities?.Remove(organizationId);
 
         return Task.FromResult(0);
     }
 
     public virtual Task DeleteProviderAbilityAsync(Guid providerId)
     {
-        if (_providerAbilities != null && _providerAbilities.ContainsKey(providerId))
-        {
-            _providerAbilities.Remove(providerId);
-        }
+        _providerAbilities?.Remove(providerId);
 
         return Task.FromResult(0);
     }
diff --git a/src/Core/Services/Implementations/LicensingService.cs b/src/Core/Services/Implementations/LicensingService.cs
index dd603b4b63..2d91017ce2 100644
--- a/src/Core/Services/Implementations/LicensingService.cs
+++ b/src/Core/Services/Implementations/LicensingService.cs
@@ -182,9 +182,8 @@ public class LicensingService : ILicensingService
 
         // Only check once per day
         var now = DateTime.UtcNow;
-        if (_userCheckCache.ContainsKey(user.Id))
+        if (_userCheckCache.TryGetValue(user.Id, out var lastCheck))
         {
-            var lastCheck = _userCheckCache[user.Id];
             if (lastCheck < now && now - lastCheck < TimeSpan.FromDays(1))
             {
                 return user.Premium;
diff --git a/src/Core/Services/Implementations/SendGridMailDeliveryService.cs b/src/Core/Services/Implementations/SendGridMailDeliveryService.cs
index a35d119970..ea915b56f2 100644
--- a/src/Core/Services/Implementations/SendGridMailDeliveryService.cs
+++ b/src/Core/Services/Implementations/SendGridMailDeliveryService.cs
@@ -72,8 +72,8 @@ public class SendGridMailDeliveryService : IMailDeliveryService, IDisposable
         msg.SetOpenTracking(false);
 
         if (message.MetaData != null &&
-            message.MetaData.ContainsKey("SendGridBypassListManagement") &&
-            Convert.ToBoolean(message.MetaData["SendGridBypassListManagement"]))
+            message.MetaData.TryGetValue("SendGridBypassListManagement", out var sendGridBypassListManagement) &&
+            Convert.ToBoolean(sendGridBypassListManagement))
         {
             msg.SetBypassListManagement(true);
         }
diff --git a/src/Core/Services/Implementations/UserService.cs b/src/Core/Services/Implementations/UserService.cs
index 5ee29171bf..bf90190ee6 100644
--- a/src/Core/Services/Implementations/UserService.cs
+++ b/src/Core/Services/Implementations/UserService.cs
@@ -357,12 +357,12 @@ public class UserService : UserManager<User>, IUserService, IDisposable
     public async Task SendTwoFactorEmailAsync(User user, bool authentication = true)
     {
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.Email);
-        if (provider == null || provider.MetaData == null || !provider.MetaData.ContainsKey("Email"))
+        if (provider == null || provider.MetaData == null || !provider.MetaData.TryGetValue("Email", out var emailValue))
         {
             throw new ArgumentNullException("No email.");
         }
 
-        var email = ((string)provider.MetaData["Email"]).ToLowerInvariant();
+        var email = ((string)emailValue).ToLowerInvariant();
         var token = await base.GenerateTwoFactorTokenAsync(user,
             CoreHelpers.CustomProviderName(TwoFactorProviderType.Email));
 
@@ -390,12 +390,12 @@ public class UserService : UserManager<User>, IUserService, IDisposable
     public async Task<bool> VerifyTwoFactorEmailAsync(User user, string token)
     {
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.Email);
-        if (provider == null || provider.MetaData == null || !provider.MetaData.ContainsKey("Email"))
+        if (provider == null || provider.MetaData == null || !provider.MetaData.TryGetValue("Email", out var emailValue))
         {
             throw new ArgumentNullException("No email.");
         }
 
-        var email = ((string)provider.MetaData["Email"]).ToLowerInvariant();
+        var email = ((string)emailValue).ToLowerInvariant();
         return await base.VerifyTwoFactorTokenAsync(user,
             CoreHelpers.CustomProviderName(TwoFactorProviderType.Email), token);
     }
@@ -453,12 +453,12 @@ public class UserService : UserManager<User>, IUserService, IDisposable
         var keyId = $"Key{id}";
 
         var provider = user.GetTwoFactorProvider(TwoFactorProviderType.WebAuthn);
-        if (!provider?.MetaData?.ContainsKey("pending") ?? true)
+        if (provider?.MetaData is null || !provider.MetaData.TryGetValue("pending", out var pendingValue))
         {
             return false;
         }
 
-        var options = CredentialCreateOptions.FromJson((string)provider.MetaData["pending"]);
+        var options = CredentialCreateOptions.FromJson((string)pendingValue);
 
         // Callback to ensure credential ID is unique. Always return true since we don't care if another
         // account uses the same 2FA key.
@@ -1353,14 +1353,14 @@ public class UserService : UserManager<User>, IUserService, IDisposable
     public void SetTwoFactorProvider(User user, TwoFactorProviderType type, bool setEnabled = true)
     {
         var providers = user.GetTwoFactorProviders();
-        if (!providers?.ContainsKey(type) ?? true)
+        if (providers is null || !providers.TryGetValue(type, out var provider))
         {
             return;
         }
 
         if (setEnabled)
         {
-            providers[type].Enabled = true;
+            provider.Enabled = true;
         }
         user.SetTwoFactorProviders(providers);
 
diff --git a/src/Core/Utilities/CoreHelpers.cs b/src/Core/Utilities/CoreHelpers.cs
index eaf1f9fbba..14a2ec35e5 100644
--- a/src/Core/Utilities/CoreHelpers.cs
+++ b/src/Core/Utilities/CoreHelpers.cs
@@ -637,9 +637,9 @@ public static class CoreHelpers
             return null;
         }
 
-        if (!globalSettings.SelfHosted && httpContext.Request.Headers.ContainsKey(RealConnectingIp))
+        if (!globalSettings.SelfHosted && httpContext.Request.Headers.TryGetValue(RealConnectingIp, out var realConnectingIp))
         {
-            return httpContext.Request.Headers[RealConnectingIp].ToString();
+            return realConnectingIp.ToString();
         }
 
         return httpContext.Connection?.RemoteIpAddress?.ToString();
diff --git a/src/Core/Utilities/LoggerFactoryExtensions.cs b/src/Core/Utilities/LoggerFactoryExtensions.cs
index 362ca22d34..b2388bc499 100644
--- a/src/Core/Utilities/LoggerFactoryExtensions.cs
+++ b/src/Core/Utilities/LoggerFactoryExtensions.cs
@@ -46,7 +46,7 @@ public static class LoggerFactoryExtensions
             {
                 return true;
             }
-            var eventId = e.Properties.ContainsKey("EventId") ? e.Properties["EventId"].ToString() : null;
+            var eventId = e.Properties.TryGetValue("EventId", out var eventIdValue) ? eventIdValue.ToString() : null;
             if (eventId?.Contains(Constants.BypassFiltersEventId.ToString()) ?? false)
             {
                 return true;
diff --git a/src/Core/Vault/Services/Implementations/AzureAttachmentStorageService.cs b/src/Core/Vault/Services/Implementations/AzureAttachmentStorageService.cs
index 20e4816662..89b152a645 100644
--- a/src/Core/Vault/Services/Implementations/AzureAttachmentStorageService.cs
+++ b/src/Core/Vault/Services/Implementations/AzureAttachmentStorageService.cs
@@ -251,16 +251,17 @@ public class AzureAttachmentStorageService : IAttachmentStorageService
 
     private async Task InitAsync(string containerName)
     {
-        if (!_attachmentContainers.ContainsKey(containerName) || _attachmentContainers[containerName] == null)
+        if (!_attachmentContainers.TryGetValue(containerName, out var attachmentContainer) || attachmentContainer == null)
         {
-            _attachmentContainers[containerName] = _blobServiceClient.GetBlobContainerClient(containerName);
+            attachmentContainer = _blobServiceClient.GetBlobContainerClient(containerName);
+            _attachmentContainers[containerName] = attachmentContainer;
             if (containerName == "attachments")
             {
-                await _attachmentContainers[containerName].CreateIfNotExistsAsync(PublicAccessType.Blob, null, null);
+                await attachmentContainer.CreateIfNotExistsAsync(PublicAccessType.Blob, null, null);
             }
             else
             {
-                await _attachmentContainers[containerName].CreateIfNotExistsAsync(PublicAccessType.None, null, null);
+                await attachmentContainer.CreateIfNotExistsAsync(PublicAccessType.None, null, null);
             }
         }
     }
diff --git a/src/Core/Vault/Services/Implementations/CipherService.cs b/src/Core/Vault/Services/Implementations/CipherService.cs
index 605061a98e..cf4e1fda86 100644
--- a/src/Core/Vault/Services/Implementations/CipherService.cs
+++ b/src/Core/Vault/Services/Implementations/CipherService.cs
@@ -312,13 +312,11 @@ public class CipherService : ICipherService
             }
 
             var attachments = cipher.GetAttachments();
-            if (!attachments.ContainsKey(attachmentId))
+            if (!attachments.TryGetValue(attachmentId, out var originalAttachmentMetadata))
             {
                 throw new BadRequestException($"Cipher does not own specified attachment");
             }
 
-            var originalAttachmentMetadata = attachments[attachmentId];
-
             if (originalAttachmentMetadata.TempMetadata != null)
             {
                 throw new BadRequestException("Another process is trying to migrate this attachment");
@@ -395,12 +393,11 @@ public class CipherService : ICipherService
     {
         var attachments = cipher?.GetAttachments() ?? new Dictionary<string, CipherAttachment.MetaData>();
 
-        if (!attachments.ContainsKey(attachmentId))
+        if (!attachments.TryGetValue(attachmentId, out var data))
         {
             throw new NotFoundException();
         }
 
-        var data = attachments[attachmentId];
         var response = new AttachmentResponseData
         {
             Cipher = cipher,
diff --git a/src/Events/Controllers/CollectController.cs b/src/Events/Controllers/CollectController.cs
index 5e0417586f..5eb48a2688 100644
--- a/src/Events/Controllers/CollectController.cs
+++ b/src/Events/Controllers/CollectController.cs
@@ -69,9 +69,9 @@ public class CollectController : Controller
                         continue;
                     }
                     Cipher cipher = null;
-                    if (ciphersCache.ContainsKey(eventModel.CipherId.Value))
+                    if (ciphersCache.TryGetValue(eventModel.CipherId.Value, out var cachedCipher))
                     {
-                        cipher = ciphersCache[eventModel.CipherId.Value];
+                        cipher = cachedCipher;
                     }
                     else
                     {
@@ -96,10 +96,7 @@ public class CollectController : Controller
                             continue;
                         }
                     }
-                    if (!ciphersCache.ContainsKey(eventModel.CipherId.Value))
-                    {
-                        ciphersCache.Add(eventModel.CipherId.Value, cipher);
-                    }
+                    ciphersCache.TryAdd(eventModel.CipherId.Value, cipher);
                     cipherEvents.Add(new Tuple<Cipher, EventType, DateTime?>(cipher, eventModel.Type, eventModel.Date));
                     break;
                 case EventType.Organization_ClientExportedVault:
diff --git a/src/Events/Program.cs b/src/Events/Program.cs
index 6b53e4b18c..967e94ed83 100644
--- a/src/Events/Program.cs
+++ b/src/Events/Program.cs
@@ -22,8 +22,8 @@ public class Program
                             return e.Level >= globalSettings.MinLogLevel.EventsSettings.IdentityToken;
                         }
 
-                        if (e.Properties.ContainsKey("RequestPath") &&
-                            !string.IsNullOrWhiteSpace(e.Properties["RequestPath"]?.ToString()) &&
+                        if (e.Properties.TryGetValue("RequestPath", out var requestPath) &&
+                            !string.IsNullOrWhiteSpace(requestPath?.ToString()) &&
                             (context.Contains(".Server.Kestrel") || context.Contains(".Core.IISHttpServer")))
                         {
                             return false;
diff --git a/src/Icons/Services/DomainMappingService.cs b/src/Icons/Services/DomainMappingService.cs
index b41d48233f..21254b6d73 100644
--- a/src/Icons/Services/DomainMappingService.cs
+++ b/src/Icons/Services/DomainMappingService.cs
@@ -13,9 +13,9 @@ public class DomainMappingService : IDomainMappingService
 
     public string MapDomain(string hostname)
     {
-        if (_map.ContainsKey(hostname))
+        if (_map.TryGetValue(hostname, out var mappedDomain))
         {
-            return _map[hostname];
+            return mappedDomain;
         }
 
         return hostname;
diff --git a/src/Identity/IdentityServer/RequestValidators/TwoFactorAuthenticationValidator.cs b/src/Identity/IdentityServer/RequestValidators/TwoFactorAuthenticationValidator.cs
index 000f98c006..e4c1ebd15e 100644
--- a/src/Identity/IdentityServer/RequestValidators/TwoFactorAuthenticationValidator.cs
+++ b/src/Identity/IdentityServer/RequestValidators/TwoFactorAuthenticationValidator.cs
@@ -240,7 +240,7 @@ public class TwoFactorAuthenticationValidator(
 
     private bool OrgUsing2fa(IDictionary<Guid, OrganizationAbility> orgAbilities, Guid orgId)
     {
-        return orgAbilities != null && orgAbilities.ContainsKey(orgId) &&
-               orgAbilities[orgId].Enabled && orgAbilities[orgId].Using2fa;
+        return orgAbilities != null && orgAbilities.TryGetValue(orgId, out var orgAbility) &&
+               orgAbility.Enabled && orgAbility.Using2fa;
     }
 }
diff --git a/src/Identity/Startup.cs b/src/Identity/Startup.cs
index 2d8ca55def..baaf9385af 100644
--- a/src/Identity/Startup.cs
+++ b/src/Identity/Startup.cs
@@ -120,9 +120,9 @@ public class Startup
                         // Pass domain_hint onto the sso idp
                         context.ProtocolMessage.DomainHint = context.Properties.Items["domain_hint"];
                         context.ProtocolMessage.Parameters.Add("organizationId", context.Properties.Items["organizationId"]);
-                        if (context.Properties.Items.ContainsKey("user_identifier"))
+                        if (context.Properties.Items.TryGetValue("user_identifier", out var userIdentifier))
                         {
-                            context.ProtocolMessage.SessionState = context.Properties.Items["user_identifier"];
+                            context.ProtocolMessage.SessionState = userIdentifier;
                         }
 
                         if (context.Properties.Parameters.Count > 0 &&
diff --git a/test/Common/AutoFixture/SutProvider.cs b/test/Common/AutoFixture/SutProvider.cs
index fefe6c3ebf..4b6f268ac3 100644
--- a/test/Common/AutoFixture/SutProvider.cs
+++ b/test/Common/AutoFixture/SutProvider.cs
@@ -27,9 +27,9 @@ public class SutProvider<TSut> : ISutProvider
         => SetDependency(typeof(T), dependency, parameterName);
     public SutProvider<TSut> SetDependency(Type dependencyType, object dependency, string parameterName = "")
     {
-        if (_dependencies.ContainsKey(dependencyType))
+        if (_dependencies.TryGetValue(dependencyType, out var dependencyForType))
         {
-            _dependencies[dependencyType][parameterName] = dependency;
+            dependencyForType[parameterName] = dependency;
         }
         else
         {
@@ -46,12 +46,11 @@ public class SutProvider<TSut> : ISutProvider
         {
             return _dependencies[dependencyType][parameterName];
         }
-        else if (_dependencies.ContainsKey(dependencyType))
+        else if (_dependencies.TryGetValue(dependencyType, out var knownDependencies))
         {
-            var knownDependencies = _dependencies[dependencyType];
             if (knownDependencies.Values.Count == 1)
             {
-                return _dependencies[dependencyType].Values.Single();
+                return knownDependencies.Values.Single();
             }
             else
             {
diff --git a/util/Setup/Program.cs b/util/Setup/Program.cs
index 50f3046d6d..921c32f5e6 100644
--- a/util/Setup/Program.cs
+++ b/util/Setup/Program.cs
@@ -20,30 +20,29 @@ public class Program
 
         ParseParameters();
 
-        if (_context.Parameters.ContainsKey("q"))
+        if (_context.Parameters.TryGetValue("q", out var q))
         {
-            _context.Quiet = _context.Parameters["q"] == "true" || _context.Parameters["q"] == "1";
+            _context.Quiet = q == "true" || q == "1";
         }
-        if (_context.Parameters.ContainsKey("os"))
+        if (_context.Parameters.TryGetValue("os", out var os))
         {
-            _context.HostOS = _context.Parameters["os"];
+            _context.HostOS = os;
         }
-        if (_context.Parameters.ContainsKey("corev"))
+        if (_context.Parameters.TryGetValue("corev", out var coreVersion))
         {
-            _context.CoreVersion = _context.Parameters["corev"];
+            _context.CoreVersion = coreVersion;
         }
-        if (_context.Parameters.ContainsKey("webv"))
+        if (_context.Parameters.TryGetValue("webv", out var webVersion))
         {
-            _context.WebVersion = _context.Parameters["webv"];
+            _context.WebVersion = webVersion;
         }
-        if (_context.Parameters.ContainsKey("keyconnectorv"))
+        if (_context.Parameters.TryGetValue("keyconnectorv", out var keyConnectorVersion))
         {
-            _context.KeyConnectorVersion = _context.Parameters["keyconnectorv"];
+            _context.KeyConnectorVersion = keyConnectorVersion;
         }
-        if (_context.Parameters.ContainsKey("stub"))
+        if (_context.Parameters.TryGetValue("stub", out var stub))
         {
-            _context.Stub = _context.Parameters["stub"] == "true" ||
-                _context.Parameters["stub"] == "1";
+            _context.Stub = stub == "true" || stub == "1";
         }
 
         Helpers.WriteLine(_context);
@@ -68,18 +67,18 @@ public class Program
 
     private static void Install()
     {
-        if (_context.Parameters.ContainsKey("letsencrypt"))
+        if (_context.Parameters.TryGetValue("letsencrypt", out var sslManagedLetsEncrypt))
         {
             _context.Config.SslManagedLetsEncrypt =
-                _context.Parameters["letsencrypt"].ToLowerInvariant() == "y";
+                sslManagedLetsEncrypt.ToLowerInvariant() == "y";
         }
-        if (_context.Parameters.ContainsKey("domain"))
+        if (_context.Parameters.TryGetValue("domain", out var domain))
         {
-            _context.Install.Domain = _context.Parameters["domain"].ToLowerInvariant();
+            _context.Install.Domain = domain.ToLowerInvariant();
         }
-        if (_context.Parameters.ContainsKey("dbname"))
+        if (_context.Parameters.TryGetValue("dbname", out var database))
         {
-            _context.Install.Database = _context.Parameters["dbname"];
+            _context.Install.Database = database;
         }
 
         if (_context.Stub)