Context menu shell extensions installed on Windows 11 for "Just me" aren't showing up

Question

I have a few shell extension programs that have installed without significant issues for many years. The setups are produced using Microsoft Visual Studio Installer Project (2022).

I've just discovered that under Windows 11, if I install them for "Just me", the context menu items don't appear (in the old classic "Show more options") context menu. I don't expect them to appear in the new Win11 context menu. If I install as "Everyone", then the context menu items do appear. I can't immediately see anything amiss with the installed registry settings or file system that would explain why the "Just me" installation doesn't show the context menu .I've had no such issues with Windows 10 (or earlier)!

On further examination, it would appear that Windows 11 may be ignoring the per-user registry setting of the extension - under HKEY_CURRENT_USER\Software\Classes\CLSID{MyGuidHere} - when I manually add the same keys/values under HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID{MyGuidhere} the context menu will appear.

Has anyone else encountered this behaviour with Windows 11?