Allow to remove whole groups via UI

[letmaik]

I need to be able to remove whole groups and not just single layers via the user interface. I could imagine that when it's enabled ("removable") for a group, then a remove symbol appears next to the collapse/expand symbol. Is that easy to implement?

[davicustodio]

@neothemachine I spent a while trying to see the size of the effort to implement it.

The problem is that the html tag that displays the title of the group is an input:

And as my knowledge in css and html are precarious, I have not found a solution to patch the code by placing a button (input) within the same input tag.

I hope that some good colleague to appear in html and css it is willing to examine the problem more appropriately.