Mabox Linux 21.04, in addition to all updates from the stable branch and a few minor fixes, brings two ISO images with LTS kernels in versions 5.10 and 5.4 (which may offer better support for some older hardware)
Known issues/bugs and fixes/workarounds
Notifications default style looks ugly
Go to Main Menu → Mabox Config → Notifications and set style as you like.
Fixed in profile for future iso refresh.