'Banking Protection 2.160.3975' for 'Firefox 45.0.1' Add-on is disabled but still turning on when opening a banking site.
Does the 'Internet Security' Tool Settings override the Add-on?
"Browsing Protection"-extension/addon required for HTTPS-support mainly.
This is mean: Browsing Protection (rating pictures, banking protection, protection against malicious websites, content blocker) work, when you have disabled/not installed addons/extension too.
But if you want to get rating pictures for HTTPS search results (Google HTTPS, Bing HTTPS, Yahoo HTTPS)... so... when extension is disabled - rating pictures for search-results will be missing.
But you still able to get search results by using HTTP-Bing (or if you will be able to use Google/Yahoo HTTP - but this search providers goes to do redirect to HTTPS).
Also... potentially extensions will be helpful for blocking or block under HTTPS-page (such as... HTTPS-site have malicious content). Or simply normal work with HTTPS and Protection features (with privacy of course).
Some other features also maybe based on extensions, but mainly https-support.
This is why "disabled" status for Browsing Protection extension will be helpful with troubles about Google-Sheet. Google have HTTPS under their pages and feature about "Show rating for search results" (which maybe comes to play there randomly) will be work.
There possible to "disable" extension (and as result HTTPS-support will be not work; and as result rating-pictures under https-search) or uncheck option about "Show rating pictures for search results" (where other potential protection-points of extensions will be work anyway, but Google Sheets will be work too - because search results "should not be shown").
Sorry for my reply. Probably there should be just normal response by F-Secure team.
My words is just my dreams about it.
And sorry for my not nice English. and for long reply.