Hi Bob,
I just signed out, then logged into the forums again with a non-moderator user account.
I discovered that only the desktop and mobile are available (both dark-ish in appearance)
When in MOBILE, I scroll to the bottom of the page and there is a link to Full Site (not seen in your screengrab)
It seems that the vB4 is just in the mod/admin menu (who knew?!)
I’m on an iPad mini and am probably behind in updating stuff.
You know, ...if it ain’t broke...n' all.
The latest iOS supports "dark mode". I don’t know if that relates to this discussion...
Except in bright sun, I use the app in "night mode" and I use the forums (full site) in a browser tab (safari)
I’m aware that mobile offers less functions the full version.
Sorry about the issue. This discussion has pretty much exhausted my technical skill set.
Perhaps an email to:
support@irealpro.com might help.
Be sure to reference this thread
https://forums.irealpro.com/threads/How-do-I-get-the-traditional-website-skin-The-light-one.25645/
It’s entirely possible that vBulletin updated their product and made it ..."better".
Most humans (me too) have an innate resistance to change.

)BOB