Firefox Community Forum

I've just now noticed that whenever I open the website hxxps://www.hex-rays.com it will hang without finishing loading for a couple of seconds, then the entire browser will freeze. I've already tried on a new profile, verified that no addons or plugins are installed there, and no DLLs hooked into the process. This happens on my physical PC and in an (almost unused) VM, with an ancient version 134.0 and the latest 149.0.

Can anyone else replicate this? Should I create a bug report?

Lately I can not click all of my browser tabs, only some of them unless I do not have the browser maximized on the screen. If I make is smaller then I can click all of the tabs. Since the recent Firefox update I can't find a hardware acceleration setting to toggle off to see if it helps.

The window is not coming, up. shut it down with task mgr. Deleted xul.json file and it worked for a little while. but broke toady. Windows update done andn restarted.

Recently, after I did a practically factory reset (using the restore from other device option once the system restart finished) and re-installing many apps, such as Firefox, despite my computer getting faster my Firefox now lags whenever I have Youtube running in the background (audio or picture-in-picture, both lag) at least during gaming. I have tried disabling GPU acceleration, with no luck, and have tried utilising picture-in-picture, which also failed. I'd appreciate any help on solving this.

im playing farmville 2 in zynga games online but it plays very slow ans keeps freezing. ive done what was recommened but there is no change to the game, i was wondering if you could help by telling me if there is anything i need to do in the browser to get this game working better

Places where I've observed this behaviour:

• The 4th video in the description of https://store.steampowered.com/app/1363080/Manor_Lords/ (ignore the media carousel at the top of the page)
• This video https://dolphin-emu.org/m/user/blog/progress-report/2603/rebelstrike-texturestreaming-av1.webm that's loaded in an embed at https://dolphin-emu.org/blog/2026/03/12/dolphin-progress-report-release-2603/

When these videos are in view and playing, they're decoded using the CPU and the browsers frame rate tanks (heavy/laggy scrolling when scrolling with mouse scroll wheel), I have a Geforce 3070 which includes support for AV1 decoding so I'm not sure what's happening.

AV1 videos found on Youtube like https://www.youtube.com/watch?v=foqVJq-XPTg are fully hardware accelerated by the GPU (Stats for nerds confirms it's playing an AV1 copy) and doesn't exhibit any performance issue.

GPU usage is monitored by Task Manager in Windows 10. For the problematic videos the GPU Decoding is at 0% with a workload being spread across many of the CPU cores. For the non-problematic 4K video the GPU Decoding is around 60-70% and no workload is distributed across multiple CPU cores.