Video group : merge group should be available
Description
During action mode, when you select 2 groups or more, you should be able to merge these groups.
See !739 (merged)
Expected behavior
It's the same to select the "Add to group" option and select one the the selected group to merge them, but it's maybe more comprehensive for users to have à "merge" option directly.
Screenshot / video
App mode
Smartphone
TV