We've upgraded our staging site from 2.4.5 to 2.6.3+ today and after having added all the missing plugins and passed that stage successfully, Moodle did load but in plain HTML (no theme, no css). Please see the screenshot below.
Does anyone have any ideas why this happens?
I've also selected the Standard theme from my Profile Settings and purged all caches after that but didn't solve the problem.
Also, on the very top of the site homepage there is a "di" "Skip to main content" thing which I don't quite understand why it appears there (please see second screenshot)
Any help would be highly appreciated!
Thank you in advance!