Background Job Management UI for file operations

Background Job Management UI for file operations: If you copy/move some large files and then refresh the page, the progressbar will disappear and the user cannot tell if the copy operation has completed other than specifically compare filesize between src and dst folder. They cannot cancel the operation because there is no such button to allow them to do so either. Also if you copy really large folders(like the one with 40GB files), the UI will say "File Cannot Be Copied" (I guess maybe nextcloud UI tell the user operation failed after a certain timeout), but in fact the copy...