Bulk actions - Always show a valid number of documents affected

Using Web UI 3.0.9 RC 9
When launching a bulk action, a notification shows "[action name] is running (0/0)" before displaying the actual number of documents being affected.

In poor conditions this information can stay on display for almost 40 seconds (tested on my local docker instance with 150k docs), which makes it very confusing and leads me to think something went wrong.

=> Expected: don't show the (0/0). Only show document numbers when the information has been computed.