And I really mean move, not copy.
The difference between copy and move is that copy... copies, but move dies copy->verify->delete original, in a single operation of the user.
Preferably, that is reliable.
Meaning it checks the bookmarks have been successfully created before closing the related tab.
Also it should be clear what bookmark folder it is going to put the tabs in.
Because the current bookmark manager, it is easy to end up dumping all your tabs in the parent folder of tge destination you indented.
Or end up creating an extra child folder inside your intended destination bookmark folder
Would also be nice to have quality of life features, such as a default bookmark folder.
The option to put the bookmarks in a folder named with today's date.
Maybe an option to specify a default destination bookmarks folder on a per site domain basis
Tab Stash seems to be what you're looking for.
It looks good, but last time I tried it, it seemed to make heavy use of the tab hiding function, which really bothers me for some reason. They seem to have added a lot of stuff, I'll give it another try ! Thanks for the suggestion.