Display a hint to show incompatible extensions in the repository catalog (see #5053)
Update README.md

Bump the version number in the installation directory name.
Merge pull request #5630 from xchs/patch-2
Do not mark request parameters as used in `Frontend::addToUrl()`
Ignore files in `.tx/purge`
Update all language files
Update SwiftMailer to version 4.3.1
Throw an exception if the database connection cannot be established (see #4071)
Remove ACE files not needed in Contao
More robust .xlf to .php conversion