Firefox Community Forum

I'm running Firefox under Ubuntu which is using Wayland which replaced X11.

Firefox's User Agent string still refers to X11, this does not cause me any problem but I'm curious.

I realise some websites might be expecting to see "X11" and could get upset if presented with "Wayland" instead but in various walks of life telling the truth is often the best policy.

about:support in Firefox shows me:

User Agent Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.0 Window Protocol wayland

macOS Tahoe, Firefox 152.0.3 macOS settings include "Appearance - Auto"; i.e. system switches from light to dark at sunset. While the "top area" (tabs, address bar, bookmarks bar) of Firefox follows this - some of the pages themselves do NOT???

I found this website which was at top of the search results. I tried to follow it, but it seems to be badly outdated in certain key respects: esp wrt a setting called "ui.systemUsesDarkTheme" in about:config. I set this to "True", but may have screwed this up!! First question: Should I "reset" this somehow?

Finally: To get at the primary question, there are two "sub-questions" that may explain my confusion more clearly:

1. Is there no ***simple way*** to get Firefox & webpages I view to follow macOS Light/Dark appearance?? What are the CORRECT steps?

2. Do individual webpages have the ability to "decide for themselves" whether or not they will adhere to the system light/dark settings. This may well be an officially "stupid question", but while "most" webpages remain "Light" (including this Support page), a few pages appear dark.

Thanks, ~S

Fonts are not scaled correctly. Too big and overlapping and too small on same page. Not scaling to fit page. Worse on Youtube and gmail. Screen shot is from this page!

I have Windows 10 a decent Lenovo laptop

I am fed up having to update firefox every single day !! Is it not completing the update or is there some glitch that keeps occurring ??

I have used FF for quite a while and ignored MicroSoft Edge... but I dont know how much longer I can carry on with this slowdown !!

Why am I suddenly receiving this error message when signing onto explore.org live camera feed. Error message is "Playback isn't supported on this device". i am able to play other videos on you tube,etc. How can I fix this?

Hello Firefox Support Team/Forum

I am writing to request guidance on a hardware video acceleration issue that I have been unable to resolve despite extensive troubleshooting. Firefox appears to be blocking VA-API hardware decoding on my system even though the VA-API stack is confirmed working at the system level. — SYSTEM SPECIFICATIONS — OS: Arch Linux (rolling), kernel 7.0.13-arch1-1 Desktop: Hyprland 0.55.4 (Wayland, DRM backend) CPU: AMD A9-9425 (2 cores, 3.1GHz, Excavator architecture) RAM: 8GB Firefox: installed via pacman (native, not Flatpak) Mesa: 26.1.3-arch1.2 GPU setup (dual): • card0 / renderD128: AMD Stoney R5 Graphics (iGPU) — VA-API confirmed working here • card1 / renderD129: AMD Hainan R5 M435 (dGPU) — used by Hyprland for display output — CONFIRMED WORKING AT SYSTEM LEVEL — Running ‘vainfo’ on the integrated GPU (renderD128) confirms the following profiles are available: VAProfileH264ConstrainedBaseline, VAProfileH264Main, VAProfileH264High (VLD + EncSlice) VAProfileHEVCMain, VAProfileHEVCMain10 (VLD) VAProfileMPEG2Simple, VAProfileMPEG2Main, VAProfileVC1 (VLD) VAProfileJPEGBaseline (VLD) MPV with ‘–hwdec=vaapi-copy’ successfully hardware-decodes H264 locally, confirmed by ‘nv12’ pixel format output and reduced CPU usage. radeontop monitoring card0 (stoney, bus 00) during Firefox video playback shows: • Graphics pipe: ~53% (compositing activity) • UVD row: absent / 0% (no hardware video decode activity) • Memory clock: near 0.00G This confirms Firefox is NOT using the hardware decoder despite VA-API being functional. — FIREFOX DECISION LOG (from about:support) — HARDWARE_VIDEO_DECODING: default available / user force_enabled H264_HW_DECODE: default available (no blocklist) HEVC_HW_DECODE: default available VP8_HW_DECODE: env blocklisted — FEATURE_FAILURE_VIDEO_DECODING_MISSING VP9_HW_DECODE: env blocklisted — FEATURE_FAILURE_VIDEO_DECODING_MISSING AV1_HW_DECODE: env blocklisted — FEATURE_FAILURE_VIDEO_DECODING_MISSING DMABUF_SURFACE_EXPORT: env blocked — FEATURE_FAILURE_BROKEN_DRIVER WEBRENDER_COMPOSITOR: env blocklisted — FEATURE_FAILURE_WEBRENDER_COMPOSITOR_DISABLED Note: VP8/VP9/AV1 being missing is expected and correct for this GPU generation. The concern is that H264, which IS in the vainfo profile list and shows as ‘available’ in the decision log, is still not being routed to the hardware decoder in practice. — ENVIRONMENT VARIABLES IN USE — MOZ_ENABLE_WAYLAND=1 LIBVA_DRIVER_NAME=radeonsi LIBVA_DRM_DEVICE=/dev/dri/renderD128 MOZ_DISABLE_RDD_SANDBOX=1 — about:config SETTINGS CURRENTLY SET — media.ffmpeg.vaapi.enabled = true media.hardware-video-decoding.force-enabled = true media.hardware-video-decoding-vulkan.enabled = false media.rdd-process.enabled = true — WHAT WAS TRIED — 1. Installed full Mesa stack: mesa, libva-mesa-driver, libva-utils, ffmpeg, vulkan-radeon (64-bit and 32-bit variants via multilib). 2. Set LIBVA_DRM_DEVICE=/dev/dri/renderD128 to hardcode VA-API to the stoney iGPU and prevent it from accidentally targeting the hainan dGPU (which fails Firefox’s internal VA-API test with FEATURE_FAILURE_VIDEO_DECODING_TEST_FAILED). 3. Enabled media.ffmpeg.vaapi.enabled and media.hardware-video-decoding.force-enabled in about:config. 4. Disabled MOZ_DISABLE_RDD_SANDBOX via both ~/.bash_profile and hl.env() in the Hyprland Lua config to allow Firefox’s RDD process to access /dev/dri/renderD128. 5. Installed enhancedH264ify extension with VP9 and AV1 blocking enabled. YouTube confirms H264 (avc1.64002a) is being served. Despite this, over 1100 frames out of ~4200 are dropped during 1080p60 playback. 6. Verified with radeontop -b 0 (stoney, bus 00) during active 1080p H264 playback: the UVD block shows no activity whatsoever, confirming the CPU is doing all decoding. 7. Tested with and without gfx.webrender.all = true. Enabling it caused severe visual corruption (texture artifacts, split UI elements), so it was reset to default. 8. Did NOT disable media.rdd-process.enabled (correctly kept at true, as RDD is the process Firefox uses for VA-API decoding). 9. Confirmed Firefox is installed via pacman (not Flatpak), so there is no Flatpak sandbox layer involved. — THE CORE QUESTION — Given that: • vainfo confirms H264 hardware decode is available on renderD128 • H264_HW_DECODE shows as ‘default available’ in Firefox’s own decision log with no blocklist entry • media.hardware-video-decoding.force-enabled is set to true • MOZ_DISABLE_RDD_SANDBOX=1 is set • LIBVA_DRM_DEVICE explicitly points to the correct render node • MPV successfully uses vaapi on the same system …why is Firefox’s RDD process still not routing H264 decoding through VA-API, and what additional steps or logs would help identify the specific internal failure point?

Any guidance on enabling verbose VA-API logging within Firefox’s RDD process, or any known issues with AMD Stoney + Hainan dual-GPU setups on Wayland that might explain the DMABUF_SURFACE_EXPORT FEATURE_FAILURE_BROKEN_DRIVER blocklist, would be greatly appreciated.

Thank you.

Firefox suddenly stopped autofilling my password on a frequently used website and nothing I do fixes the issue. I've tried all the options and followed instructions offered on the firefox help pages and nothing works. Please advise?

When I click on the Mozilla VPN app icon in the Mozilla Browser it requests that I download something rather than just turning it on. This is recent and I've never experienced it before... I have tried everything I can think of, but cannot get it to work properly...

So Firefox total changed my browser design. It has taken over my full screen. My tabs are on the side now. There is no back or forward arrows to go back to the previous web page. The add-ons are no longer visible or accessible. And there is no way to close the browser without using the task manager.

Windows 11 Pro

I recently opened this 'bug' which may involve my inadvertent use/misuse of Profiles. https://bugzilla.mozilla.org/show_bug.cgi?id=2052294

How can I locate other (older) Profiles in the Mozilla Firefox structure and use this to run an older version of Firefox ie: 132 or other Version that I consider to be more stable.

(I have already seen where it is not recommended to go to an older version, once a profile has been used on an updated version. At this time - I feel any damage has ALREADY been done & cannot make things much worse.)

In the previous version of Firefox, there was a location to save current tabs in the "Home" section is that still available? Where is it?

I've attached a photo of the current page, and there does not appear to be a "save current tabs" option

IF I click on a link in, e.g., a Disqus comment -- say, if I click on https://www.electoral-vote.com/evp2026/Items/Jul01-4.html THEN the Firefox response is to send me to, e.g., https://www.electoral-vote.com/evp2026/Items/Jul01-4.html:1K9Y2syRo30ousOmB06EENUd6jg Of course, the outcome is a "404 Not Found" error message. So exactly WHAT is the point of FF adding ":garbagecharacters" to the end of URLs, since doing so utterly *incapacitates* the functionality of "clicking on an embedded link" ?