Needs review recording from the scan and the monitor shared the capture
store's two workers with the Tag dialog and Apply, so a busy scan could
answer a user's preview or decision with "Too many previews are open".
Background captures now never take the last worker or capture slot, and
wait up to two seconds for room before counting the file as not added.
Interactive captures are admitted or refused at once, as before.
Vito Sansevero
fe5a0017a9