Added extension gallery URL causes VS to be unable to update or get info of extensions

[Trisibo]

This extension adds a gallery named "Extensibility Template Pack" and URL "https://www.vsixgallery.com/feed/extension/88049e1e-62f2-4ea2-851f-9ddb2de37f41", which generates 404 errors, and these issues:

• Visual Studio is unable to update extensions from the "Installed" and "Update" tabs of the Extension Manager.
• Visual Studio does only show a short description of any extension selected in those tabs, instead of the full page.

When running devenv /Log, trying to update any extension from those tab logs this entry:

<entry>
  <record>410</record>
  <time>2026/07/19 16:24:17.336</time>
  <type>Error</type>
  <source>VS/ExtensionManager/UI/DownloadCommand/Execute</source>
  <description>System.Net.Http.HttpRequestException: Response status code does not indicate success: 404 (Not Found).&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.Threading.ThreadingTools.&lt;WithCancellationSlow&gt;d__8`1.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.AtomRepository.&lt;LoadFeedAsync&gt;d__14.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.Threading.AwaitExtensions.ExecuteContinuationSynchronouslyAwaiter`1.GetResult()&#x000D;&#x000A;   at Microsoft.VisualStudio.Threading.AsyncLazy`1.&lt;&gt;c__DisplayClass20_0.&lt;&lt;GetValueAsync&gt;b__0&gt;d.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.Threading.AsyncLazy`1.GetValue(CancellationToken cancellationToken)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.AtomRepository.SearchImpl(String searchTerms)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.ExtensionRepositoryWrapper.SearchAsync(String searchTerms, CancellationToken cancellationToken)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.AllRepositoryOption.&lt;SearchAsync&gt;d__9.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.ExtensionProviderUtilities.&lt;UpdateMarketplaceExtensionMetadataAsync&gt;d__7.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.DownloadExtensionCommand.&lt;QueueUpdateAsync&gt;d__24.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.DownloadExtensionCommand.&lt;HandleUpdateAsync&gt;d__20.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.ExtensionManager.UI.DownloadExtensionCommand.&lt;ExecuteAsync&gt;d__18.MoveNext()&#x000D;&#x000A;--- End of stack trace from previous location where exception was thrown ---&#x000D;&#x000A;   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()&#x000D;&#x000A;   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)&#x000D;&#x000A;   at Microsoft.VisualStudio.Shell.VsTaskLibraryHelper.&lt;&gt;c.&lt;&lt;FileAndForget&gt;b__36_0&gt;d.MoveNext()</description>
</entry>

When the extension is uninstalled, the issues disappear. They reappear again when the extension is installed.

Visual Studio version 18.8.0.
Extensibility Template Pack 2022 version 2.2.64.