- Open Thunderbird.
- Click on the Hamburger to open the options list and select Preferences.
- Click on Advanced.
- On the General tab, click Config Editor.
- Agree to the Warning…blah, blah, blah.
- In the Config Editor, type or copy and paste in: network.protocol-handler.external-default
- Set this value to false.
- Restart Thunderbird.
Links will no longer show up in emails. The text for the URL will still be there, but they will no longer be clickable.
Think before you click !!!
These steps were taken from Thunderbird v52.9.1