We just published the first service release to update the stable
version 1.3 which is the result of some touching-up on the new
features introduced with the 1.3.0 release. For example it brings back
the double-click behavior to open messages which was reduced to the
list-only view. Or because the switch to change the mail view layout
was a bit hidden, we also added it to the preferences section.
The update also includes fixes to reported bugs and one potential XSS
vulnerability as well as optimizations to smoothly run on the latest
version of PHP.
See the full changelog in the release notes  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 https://roundcube.net/download.