Different theme / template being applied to different pages after upgrade
(updated for clarity)
I get a different theme applied for different menu items / screens. See https://mycuz.us/wiki. Home page is fine. But the "Contact Us" page and tiki-orphan_pages.php switch to some theme that is unreadable (same color text on same color background). When logged in, more pages with problems pop-up. Any of the tiki-admin.php pages have that same, unreadable theme. Oddly, the User Wizard page (tiki-wizard_user.php) has yet a third theme introduced that is partly unreadable.
I have not modified or set any different templates or themes. I do notice there is now a "Theme Control" admin item that allows you to change the theme based on Categories. As best I can tell, there are no entries there.
I have tried it on Chrome, Firefox and Edge — same on all. Cleared the caches. I should add the desktop host is set to Dark Theme itself and most browsers and UI's follow the system setting. Ideas?
Backgrounder:
I had to finally upgrade due to the hosting provider cutting off all PHP except v8. Went from Tikiwiki 21.2 to 26.2 on two sites (mycuz.us/wiki and h600.org/wiki). On H600, permissions got a little messed up. But that was it. But this site has three troublesome issues the other does not.Two similar sites. Both upgraded at the same time. Both on the same server. Mycuz particular site has been upgraded since ~2010. H600 since ~2015. Documenting growing list of issues not solved at https://mycuz.us/wiki/User-admin
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