No matter the settings, I could not have Mailbox Alert make any useful work in that context.
The only things having an impact on alerts behaviour are still the built-in alert settings of Thunderbird, just global settings.
No way to have a distinct behaviour for some mailboxes.
In camparizon,
proceeding the same but under WIndows 10, with Thunberbird 91 or even 102 works perfectly fine.
No matter the settings, I could not have Mailbox Alert make any useful work in that context. The only things having an impact on alerts behaviour are still the built-in alert settings of Thunderbird, just global settings. No way to have a distinct behaviour for some mailboxes.
In camparizon, proceeding the same but under WIndows 10, with Thunberbird 91 or even 102 works perfectly fine.