Why do applications open TOR when Chromium is set as the default browser?

Question

linux

Cromium is set as the default browser, and applications open links in TOR.

Answer 1

Thunderbird -> Edit -> Preferences -> Advanced -> Open Config Editor:
Set the following options to True:

network.protocol-handler.warn-external.http 
network.protocol-handler.warn-external.https

The next time you open the link, the application should ask which browser to open and there should be a "Remember" button.