diff --git a/BTCPayServer/Controllers/ManageController.2FA.cs b/BTCPayServer/Controllers/ManageController.2FA.cs
index 062b32ce9..1496711f2 100644
--- a/BTCPayServer/Controllers/ManageController.2FA.cs
+++ b/BTCPayServer/Controllers/ManageController.2FA.cs
@@ -155,7 +155,7 @@ namespace BTCPayServer.Controllers
             int currentPosition = 0;
             while (currentPosition + 4 < unformattedKey.Length)
             {
-                result.Append(unformattedKey.Substring(currentPosition, 4)).Append(" ");
+                result.Append(unformattedKey.Substring(currentPosition, 4)).Append(' ');
                 currentPosition += 4;
             }
 
diff --git a/BTCPayServer/Controllers/RateController.cs b/BTCPayServer/Controllers/RateController.cs
index f10a2ba8b..b43eb905e 100644
--- a/BTCPayServer/Controllers/RateController.cs
+++ b/BTCPayServer/Controllers/RateController.cs
@@ -157,7 +157,7 @@ namespace BTCPayServer.Controllers
             foreach (var currencyCode in currencyCodes)
             {
                 if (!first)
-                    currencyPairsBuilder.Append(",");
+                    currencyPairsBuilder.Append(',');
                 first = false;
                 currencyPairsBuilder.Append($"{baseCrypto}_{currencyCode}");
             }
diff --git a/BTCPayServer/Payments/Bitcoin/NBXplorerListener.cs b/BTCPayServer/Payments/Bitcoin/NBXplorerListener.cs
index 65c2338f2..e10a91d2a 100644
--- a/BTCPayServer/Payments/Bitcoin/NBXplorerListener.cs
+++ b/BTCPayServer/Payments/Bitcoin/NBXplorerListener.cs
@@ -207,7 +207,7 @@ namespace BTCPayServer.Payments.Bitcoin
                 {
                     Logs.PayServer.LogInformation($"Disconnected from WebSocket of NBXplorer ({network.CryptoCode})");
                     _SessionsByCryptoCode.TryRemove(network.CryptoCode, out WebsocketNotificationSession unused);
-                    if (_SessionsByCryptoCode.Count == 0 && _Cts.IsCancellationRequested)
+                    if (_SessionsByCryptoCode.IsEmpty && _Cts.IsCancellationRequested)
                     {
                         _RunningTask.TrySetResult(true);
                     }
diff --git a/BTCPayServer/Services/Invoices/InvoiceRepository.cs b/BTCPayServer/Services/Invoices/InvoiceRepository.cs
index c12c4c2eb..e50f8b40b 100644
--- a/BTCPayServer/Services/Invoices/InvoiceRepository.cs
+++ b/BTCPayServer/Services/Invoices/InvoiceRepository.cs
@@ -655,9 +655,9 @@ namespace BTCPayServer.Services.Invoices
             if (!string.IsNullOrEmpty(queryObject.TextSearch))
             {
                 var text = queryObject.TextSearch.Truncate(512);
-#pragma warning disable CA1307 // Specify StringComparison
+#pragma warning disable CA1310 // Specify StringComparison
                 query = query.Where(i => i.InvoiceSearchData.Any(data => data.Value.StartsWith(text)));
-#pragma warning restore CA1307 // Specify StringComparison
+#pragma warning restore CA1310 // Specify StringComparison
             }
 
             if (queryObject.StartDate != null)
diff --git a/Build/Common.csproj b/Build/Common.csproj
index 3735d5720..706c1d457 100644
--- a/Build/Common.csproj
+++ b/Build/Common.csproj
@@ -2,7 +2,7 @@
   <PropertyGroup>
     <TargetFramework>netcoreapp3.1</TargetFramework>
     <TargetFramework Condition="'$(TargetFrameworkOverride)' != ''">$(TargetFrameworkOverride)</TargetFramework>
-    <NoWarn>NU1701,CA1816,CA1308,CA1810,CA2208,CA1303,CA2000</NoWarn>
+    <NoWarn>NU1701,CA1816,CA1308,CA1810,CA2208,CA1303,CA2000,CA2016,CA1835,CA2249,CA9998</NoWarn>
     <LangVersion>8.0</LangVersion>
   </PropertyGroup>