This script applies to https://kar.cr. It adds APPROVE ALL, APPROVE SELECTED and DISCARD ALL buttons inside the "Torrents awaiting feedback" popup:
(by default it only has DISCARD SELECTED)

Note: You may uncomment lines 59, 76 and/or 94 to also close the popup after approving all/selected torrents.

Thanks to wOxxOm for his help in here.