hey racket, i’m having the same problem with you, i’m using 2.5.1 and same .htaccess with yours.
my problem is with page, lets say you have:
about page, with url: https://domain.com/about/
and contact page, with url: https://domain.com/contact/
the problem happen when you type url: https://domain.com/about/contact it will show all the pages content (both about and contact and others if you have more pages)
it should be show 404 page instead of showing all pages. anybody experiencing the same problem?