OK, since about 2 months recent Window updates or Dropbox updates, not sure one, Tortoise icons no longer appear.
I've been through this for years, added spaces to the icon handlers, removing onedrive and dropbox handlers, etc., and everytime I've managed to get the icons to work.
No more. Can't get Tortoise's icons to appear. I'm running the latest version of tortoisesvn with the latest version of Windows 11.