Firefox

Same, I am not facing any issues too.

I use YT every day and use Firefox as my main browser. I've never experienced this. Just tested out of curiosity, it loads fine.

Yeah it appears on chrome as well. There isn't any evidence that it's purposely "slowing down" anything. I had a quick glance at the Reddit thread (been avoiding it as much as possible, but had to visit in incognito to confirm the source for this outrage) and it looks like it's part of a small script to check if an adblocker is present and disabling video ads from playing.

It's possible FF have a delay in playing that first video, but also the test methodology isn't super reliable because of caching.

It's just typical sensationalized bullshit with people jumping to conclusions based off random ass Reddit threads. This apparently originated from the linus tech tips forums so it's probably straight bs.

I've experienced this issue firsthand, although it's more like 3 to 4 seconds. Changing the user agent to Chrome causes videos to load instantly, and restoring it to the original user agent causes the "lag".

Some possibly relevant information: I'm running Firefox with unlock Origin on Linux Mint. I've also received the "playback will be disabled after 3 videos" message in the past -- so it's possibly only affecting users they strongly suspect are still using ad-blockers with workarounds.