This has been really bothering me...
In the "List actions" menu, there are two similar options "Archive all cards in this list" and "Archive this list".
If I select "Archive all cards in this list", there is a confirmation dialog before the actions is performed.
If I select "Archive this list", the list is immediately archived.
Sometimes I select that option by mistake. To only way to undo it, the user has to go to the tiny "..." menu in the upper right -> "... More" -> Archived Items -> Switch to lists -> Send to board.
There should be a confirmation dialog before a list is archived.
I should be able to ctrl+Z to undo that action.
I should be able to undo the action from the Activity list in the root "..." menu.
Cheers!