We just published the third service release to update the stable version 1.5. It provides a bunch of small fixes and improvements for the PHP8 compatibility. See the full changelog in the release notes (https://github.com/roundcube/roundcubemail/releases/tag/1.5.3) on the Github download page.
This release is considered stable and we recommend to update all productive installations of Roundcube with this version. Download it from roundcube.net (https://roundcube.net/).
Please do backup your data before updating!
Source: https://roundcube.net/news/2022/06/26/update-1.5.3-released
Get it Now: https://roundcube.net/download