Firefox 89.0 update and video lags

[serr]

Since this update, I have video lags with Youtube. Crashy kind of lags even when fully buffered. I have plenty of CPU to spare with machines spec'd for audio work - I'm not shut down or anything. It just feels Windows-like 2nd class. Sure looks like someone screwed up! Anyone else seeing this?
Should I uninstall and install an old version?
Should I finally try a different browser app? Opinions welcome there.

I'm running 10.13.6 most of the time FYI.

 

[serr]

Nope!

It would seem that I coincidentally had my battery starting to fail. The classic MBP battery failure mode: Since the MBP can use more power than the charger can provide, this leads to trying to draw more than the battery has left. The battery is confused and telling the computer it has charge. There's a grey area of this failure mode when you also have the machine plugged into power that leads to throttling kind of lag. Probably from brown-out kind of issues.

There were earlier warnings in hindsight. It finally konked out on me on battery only and thus became apparent.

Sorry Firefox!

 

[Cayenne1]

FF 89. removed ability to sort bookmark folders individually. I reverted back to 88.0.1. You must disconnect from the internet to prevent an auto update to 89 before installing an older version. Here are the downgrade steps.

1. Download Firefox 88.0.1 installer
2. Trash 89.0
3. Disconnect from the internet
4. Install 88.0.1
5. Uncheck Preferences/Home/Automatically install Updates
6. Re-connect to the internet.
7. Ignore all Firefox update pop-ups

Also, make note of Add-ins and Extensions as you may have to re-install those as well.