Steps to reproduce:

1 - Open Thunderbird.
2 - Type search term in either of the two search fields, press enter.
3 - Status Bar continuously displays 'Searching...' and will not display any other data until a message is selected.
4 - Status Bar will also continuously display 'Searching...' if either of the search fields are cleared.

Actual results:

The search function is operating, new tabs are generated if a search term is typed into either search fields followed by pressing enter; yet the Status Bar will continue to display 'Searching...' even after the search is complete. As above, this Status Bar display can only be cleared by selecting a message from the message pane.

Expected results:

The Status Bar should have cleared itself after the search was completed, or displayed a 'Search Complete' or some other message.

ping, do you think this is also a duplicate - like the user's other bug 1760196?

I see this problem on IMAP account as well, so it's not caused by pop3-js changes.