Since the latest Firefox update to 121.0.1, it seems to have become very slow in starting to play videos and streams, often taking several seconds before showing anything other than a black rectangle. Additionally sometimes when I scroll down to the comments or chat and then back about half the image (depending how much was hidden) remains as white for an appreciable time.
Usually once it gets started it plays OK, though occasionally it can be stuttery early on.
For the record. Are you using any ad blockers in Firefox?
uBlock Origin (recommended) or Ad Block, for example?
Even with uBlock Origin, I’ve noticed lately that I must click the video container before it will play (only an empty black void is displayed otherwise. I imagine the use of other ad blockers might reveal even greater annoyances to the YouTube advertising experience.
Back to general performance … you might want to double check hardware acceleration… as well as note that current mesa has had certain proprietary bits removed … which could negatively impact amd users … especially those that would have relied on the more dated formats like h.264 .
My short answer to that is that it’s all FUD and prejudice. Let’s go over your arguments one by one…
Its much more resource hungry than alternatives.
I haven’t noticed any of that, and I’m not exactly running the latest & greatest hardware here. This is a 6-core Intel i5-8400 — real cores, no Hyperthreading™ — with 16 GiB of RAM, about 512 MiB of which is used by the integrated Intel 630 UHD GPU.
Allows ‘acceptable’ ads by default
Has working relationships with advertisers
Which can be disabled with a few simple clicks.
Less performant than alternatives
Not in my experience.
Relies more on cosmetic filters than alternatives
Does not actively develop with community input to evade anti-adblock
At this point in time, I am not seeing any ads or experiencing any slowdowns with AdBlock Plus in Firefox.
However, I am using the same AdBlock Plus in Chromium, and in Chromium I am effectively seeing static ads on YouTube, and remnants of ad videos before the main video starts playing, as well as that YouTube does indeed work slower there. And this all started after the most recent update to chromium.
So in my book, Chromium is what’s causing the problem here on my computer, which makes sense, given that it’s a Google product. At the same time, I am not getting any problems at all in Firefox, which clearly exonerates both Firefox and AdBlock Plus.
That all said, I do not know why the OP is having those problems, but it may be down to one of his other browser extensions, and it’ll definitely be related to Google/YouTube’s attempts at cracking down on ad blockers.
I tried to read that, and still don’t know anything.
YouTube’s performance issues with Adblocker / Plus could be due to a bug in Adblocker. This was particularly analyzed by Raymond Hill, the developer of the competing ad blocker uBlock Origin, in an X post.