I found the following reviews of Webshield at https://addons.mozilla.org/en-US/firefox/addon/total-webshield/reviews/

Rated 1 out of 5
by Sandy Richards, 12 hours ago
Having issues with the "real-time protection" when opening the icon. Get an error message and to reboot but after 3 days of doing this, nothing changes. Hopefully they have a money-back policy!
Rated 1 out of 5

by Firefox user 17174329, 3 days ago
12-09-21: After installing the Total Webshield extension, I was not able to log onto online banking for Bank of America and Capital One. I removed the Total Webshield extension. Immediately after removing the Total Webshield extension, I was able to log onto online banking for Bank of America and also Capital One with absolutely no issues. Something is wrong with Total Webshield.
Michael Allen