Firefox on Linux has much more problems than Firefox on Windows, mostly because it does not support many GPUs, so it frequently disables WebGL or it cannot use hardware support for playing videos, even now, in 2026. This breaks many sites.
Unlike Firefox, the Linux versions of Vivaldi/Chromium/Chrome do not appear to have any deficiencies in comparison with their Windows versions.
Whenever I encounter a broken site, it's because I blocked some advertising scripts and the whole thing fell apart with a slew of JavaScript errors. I'm quite happy to avoid such shoddy sites.
The problem is not stability, but the fact that there are multiple APIs, and it is unknown which of them will be available on the user system, so a browser may need to support all of them.
For instance, for video decoding on a GPU, the Linux APIs differ depending on the GPU vendor, unless you use Vulkan, but Vulkan video decoding is not available in old computers. Even so, Firefox could have used some higher-level API that takes care of the low-level GPU-dependent details (e.g. ffmpeg).
More baffling is the failure of Firefox to use OpenGL or Vulkan for implementing WebGL, depending on the GPU vendor, because at least the OpenGL API has not changed in a very long time. I have no idea which is the reason (because Firefox does not provide adequate error messages), unless they depend on some vendor-specific OpenGL extensions. I use an NVIDIA GPU, on which I cannot enable WebGL in Firefox, despite the fact that WebGL works fine in Vivaldi and Chromium/Chrome and I use a very great number of OpenGL and Vulkan applications, including some written by myself, all of which work perfectly, with no problems whatsoever.
Some sites also simply to not test their stuff on Firefox since it has such a small market share, and Firefox _does_ have minor incompatibilities that only tend to show up when using overly fancy Javascript or CSS frameworks. (But this is far less common than the first point above.)
ProTip: Try to do your thing in Guest Mode. It will almost certainly work there.
Have been a Vivaldi user for many years.
Vivaldi is made by people who left Opera after it was bought by a Chinese company, and the mouse gestures are similar. Ny favorites: "Hold right mouse button, click left" is the browser back gesture, and "hold left, click right" is forward.
You can tell the Vivaldi devs care about that kind of stuff. I don't want to use a chromium-based browser as my daily driver, but I like a lot of what they're doing.
You can open whatsapp web or a pdf or most other websites and just scroll. The difference is massive.
https://addons.mozilla.org/en-US/firefox/addon/print-edit-we...
vivaldi was doing something weird for me, can’t exactly remember what now. seemingly unprompted it would switch tabs or go back in history or something.
turns out i’d tried to be clever, set up a mouse gesture and forgotten about it. xD
Classic
To do list: make huge spreadsheet of hotkeys across programs and periodically feed them back to myself as flashcards based on [lack of] usage
KeyCue didn’t seem to cut it but maybe skill issue