After the last Apache Upgrade, I've had some issues with "spaces in URL" in mod_rewrite. 2023-04-25 - upgrade apache2:amd64 2.4.38-3+deb10u9 2.4.38-3+deb10u10
The URLs that contain "space" and have been replaced with %20 start to return error 403 by Apache.
I found that the update was actually to fix this: https://github.com/apache/httpd/commit/d78a166fedd9d02c23e4b71d5f53bd9b2c4b9a51
(https://security-tracker.debian.org/tracker/CVE-2023-25690 )
After the last Apache upgrade under Ubuntu, I solve the problem of returning 403 by adding [NC,L,B,BNP] at the end of the domain conf file, adn it works for me.
RewriteEngine On
RewriteBase /
RewriteRule ^([^/])/([^/])$ /index.php?lang=$1&page=$2 [NC,L,B,BNP]
I hope that this fix should be helpful to somebody :-)