# LibreWolf Stopped Playing Videos After the FFmpeg 9 Update
After a recent system update on Arch Linux, video playback in LibreWolf suddenly stopped working.
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At first, it wasn't obvious what had changed
At first, it wasn't obvious what had changed. I went through the usual possibilities, including hardware acceleration, VPN/DNS issues, browser cache, and other playback-related settings. Eventually, the timing pointed toward an FFmpeg update. LibreWolf was no longer able to play videos correctly after the system update. The important part was that normal browsing still worked. The failure was specific to media playback. That left several possible places to investigate. I started with the usual browser-side checks.
I checked hardware acceleration and browser-related settings to
I checked hardware acceleration and browser-related settings to make sure the problem wasn't caused by a configuration change inside LibreWolf. I also looked at the VPN and DNS configuration because the problem initially happened while the VPN was being used. So the VPN connection itself was completing successfully. There was also a resolvconf warning: I checked the resolver state and manually ran: That completed without producing the previous lock error, but it did not fix LibreWolf's media playback. At that point, the network configuration was looking less likely to be the cause. The investigation eventually moved toward the multimedia libraries used by LibreWolf. The important change in the system update was an FFmpeg major-version update from 8 to 9.
That timing stood out because FFmpeg major releases
That timing stood out because FFmpeg major releases can involve changes to the libraries applications depend on. If an application or package hasn't been updated for the new library interface yet, compatibility problems can occur. That matched what I was seeing. The problem was no longer looking like a VPN, DNS, browser-cache, or ordinary browser-settings issue. The FFmpeg update provided a much stronger lead. The Compatibility Problem
The evidence pointed toward a compatibility problem between
The evidence pointed toward a compatibility problem between the updated FFmpeg libraries and the LibreWolf build installed on my system. The important distinction is that this does not mean that FFmpeg 9 itself was broken.
The problem was the transition between major library
The problem was the transition between major library versions and whether the application using those libraries was ready for that change. In my case, the installed LibreWolf package had not yet caught up with the transition. I tested the compatibility theory by installing the older FFmpeg compatibility package: The ffmpeg4.4 package provides the older FFmpeg 4.4 libraries alongside the current FFmpeg package. After installing it, LibreWolf was able to play videos again. That gave me a much stronger connection between the FFmpeg transition and the playback failure. The verification was simple. I opened the same video that had previously failed. After installing ffmpeg4.4, playback worked again.
That made the compatibility explanation much more convincing
That made the compatibility explanation much more convincing than the earlier theories around VPN, DNS, hardware acceleration, or browser cache. The important sequence was:
This was also consistent with a recent Arch
This was also consistent with a recent Arch Linux forum report from August 2026 where LibreWolf video playback broke after the FFmpeg 8 → 9 update and ffmpeg4.4 was used as a temporary workaround until a LibreWolf update resolved the issue. ffmpeg4.4 is a workaround, not necessarily the permanent solution. The better long-term solution is for the affected application/package to support the newer FFmpeg libraries.
That means the compatibility package may no longer
That means the compatibility package may no longer be necessary once LibreWolf and its dependencies have caught up with the newer FFmpeg version.
I would therefore treat the older package as
I would therefore treat the older package as a temporary compatibility measure rather than something that should automatically be kept forever.
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# LibreWolf Stopped Playing Videos After the FFmpeg 9 Update
After a recent system update on Arch Linux, video playback in LibreWolf suddenly stopped working.
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Source: Dev.to