I've had uBlockOrigin, Ghostery and Disconnect installed for awhile.

I recently went through Ghostery's and Disconnect's settings, choosing the most agressive blocking. I am amazed at how quiet my laptop runs.

I recently went to a Wired article, and uBO blocked 133 requests. That's 133 bits of content or code that my browser and cpu did not have to work on.

It may not be Firefox that's causing you trouble, it may just be that the Web sucks more with each passing day.

uBO is cool- I'll be switching to it from AdBlock Plus straight away & start saving a few milliseconds on page load with its CPU usage being less.

Are these in addition to, or in lieu of Ad Block Plus?

I deleted Adblock Edge, and replaced it with uBO.

I switched from Firefox to Chrome about a year or so ago. No complaints so far. I'm not going to talk you out of it. I think it's a good idea to switch.

Multiple threading= 1 process per tab

A bit more lightweight than Firefox when both are loaded with plugins.

Why limit yourself to one browser?

I use many browsers. Though Chome tends to be my main goto on the desktop for personal stuff mainly because of the good syncing system they set up early and Opera Mobile on the phone (I dropped Chrome here as it seems to be getting worse). IE I save for work on screen presentations so you don't have browser history showing up as you type plus the odd archaic system that demands IE. I use FF for some work areas to keep separate accounts. Also FF still have the best best extensions environment. And Opera for the accounts reason too.

Another browser and possible contender for my main desktop browser is Vivaldi. While not quite there this is still early days. It's being founded by some of the old Opera Browser team. They are trying to rebuild a browser with the old core Opera values and create a power user product. Check it out: https://vivaldi.com/ I'm using this also and keeping a close eye on how it developes.

Also if your browser is bogging you down due to hardware limitation try Opera 12 (old version before the big shift). It's very resource friendly.

Disclaimer: Ex-Opera employee

I've found https://github.com/dfkt/firefox-tweaks/blob/master/firefox-t... to fix a lot of the things that piss me off about Firefox. I don't use Firebug anymore, and that change alone sped things up pretty significantly.

Are there any extensions/add ons that exist for multiple browsers that allow you to actually measure browser performance on an arbitrary site? If you had such a thing, you could easily and quantitatively test the websites you visit most often, and figure out which browser best suited your specific use case.

I disabled everything but Ghostery, since in reality I don't use Firebug much. We'll see what happens with that as the only add-on. Otherwise, I'm jumping ship. I don't mind some inconveniences, but when I can't get anything done...

How powerful is your hardware? What OS do you use? Do you have any irreplaceable extensions?

I have an 8-gig mem 64-bit Windows 7. I run almost no extensions (usually just firebug and ghostery and web developer).

It's not any one thing; it just seems to bog down, and I can't noodle out why, except Firefox seems to be the common denomator ATM.

I'm running a machine with the same specs as you and I don't ever experience Firefox bogging down as you are describing. I do believe Firefox is more heavy-weight than Chrome, but nothing to the point where I have to consider updating my OS or running an SSD. I set my browser to delete everything when I close and launch again. This helps to keep registry and temp files from building up. Perhaps this might help?

I've never been able to get firefox to play well for me from the start (for me 2008). I searched for something faster and I found opera and used that.

As is mentioned earlier, firefox does not appear to take advantage of multi-threading. I take this to mean that it's performance would be the same on a quad core cpu or a single core cpu of the same speed. There's much more to it than I know for sure, but certainly feels like it has to share resources with itself as well as anything else running. I tried it out a couple months ago and then went back to Opera/chrome. Many of the same plugins are available in chrome that are offered for firefox.

Firebug is one of the worst extensions I've seen in terms of performance. Uninstall it and see if there are changes.

Especially since devtools are native in Fx now.

Yeah, it's awful. I also stopped using in favor of the native FF tools. There's https://getfirebug.com/releases/firebug/3.0/ but it's way better to just make the switch.

If you don't have an SSD, upgrading to one would make a huge performance difference. You can also try Pale Moon and see if that works better for you.

You should certainly also upgrade to Windows 8.1 at least, if not Windows 10. There aren't any compatibility differences that I've ever noticed, and there are absolutely performance benefits.