I was beside myself for months struggling to get web browsing to be tolerable. By kismet, I disabled browser guard. The heavens opened and SpaceX launches ceased to buffer. I have used Malwarebytes for years and like it, but this extension has a heavy cost in using the internet.

It's a must-have, not just an ad blocker, but as the name suggests, it also protects against malware and scams! It's rare to make a mistake and have to turn off ad blocking - but if a reliable (!) site doesn't work, then (and only then) do it 8)
HUN: Kötelező, messze nem csak hirdetés blokkoló hanem ahogy a neve is adja malware és scam elleni védelem is! Ritkán téved és tirkán kell lekapcsolni a hirdetés blokkolást - de ha nem működik egy megbízható (!) oldal akkor (és csak akkor) tedd meg 8)
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"Crash due to high CPU usage" I hope I can fix the bug that is slowing down the browser. But I see that Firefox versions are not updated that much :\
HUN: Remélem sikerül javítani a hibát ami miatt lassítja a böngészőt. De azt látom hogy a verziókat Firefox nem frissítok annyira :\

Sadly detected/blocked by YouTube :(

I love this add-on. Sadly I can't have it enabled at all in my browser anymore because of Youtube/Googles witch hunt for adblockers. Even if I allow list youtube via the add-on Youtube stull blocks me from viewing any video at all. Completely disabling the add-on in Firefox settings and I can watch videos again :/

Lots of false positives for phishing recently. Their heuristics are NOT working properly.

"Developer response
posted 7 days ago
A factory reset of Browser Guard has resolved this issue for many users.

To do so:
Open Browser Guard
On the top right, click the 3 vertical dots
Click "Support"
Click "Factory Reset""

Wish I had seen this earlier. I was pulling my hair out trying to figure out why FF was suddenly so sluggish. It just happened to coincide with getting a new modem from Xfinity so thought that was somehow causing issues. It wasn't until I started disabling addons and got to MBG that everything returned to normal. I was prepared to just leave it disabled, but the above fix worked for me. At least if it happens again, I know where to start. I removed a star from my review for the hair pulling.