The UI for this was always a question, and UI developers are even scarcer than C# ones. Any helpers? Duplicati is a community effort, and relies on volunteers, otherwise progress doesn’t happen (or worse).
There’s actually another short part of the dropdown line possible, but would a short tag be helpful at all?
Implementing it might be done with a similar change to the dlist files, but how would one do the UI for it?
At the destination, each dlist file is a backup version, so tag editing would be tough (no database there).
If really necessary, it might be possible to leverage the code where Repair can upload deleted dlist files.
Next time it goes up, put the new tag on it. Regardless, still needs some UI and importantly, developers.