I can't get hardware h264 decoding to work on Mint FIrefox.

Vainfo shows this:

libva info: VA-API version 1.20.0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/radeonsi_drv_video.so
libva info: Found init function __vaDriverInit_1_20
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.20 (libva 2.12.0)
vainfo: Driver version: Mesa Gallium driver 24.2.8-1ubuntu1~24.04.1 for AMD Radeon R6 Graphics (radeonsi, carrizo, LLVM 19.1.1, DRM 3.57, 6.8.0-51-generic)
vainfo: Supported profile and entrypoints
VAProfileMPEG2Simple : VAEntrypointVLD
VAProfileMPEG2Main : VAEntrypointVLD
VAProfileVC1Simple : VAEntrypointVLD
VAProfileVC1Main : VAEntrypointVLD
VAProfileVC1Advanced : VAEntrypointVLD
VAProfileH264ConstrainedBaseline: VAEntrypointVLD
VAProfileH264ConstrainedBaseline: VAEntrypointEncSlice
VAProfileH264Main : VAEntrypointVLD
VAProfileH264Main : VAEntrypointEncSlice
VAProfileH264High : VAEntrypointVLD
VAProfileH264High : VAEntrypointEncSlice
VAProfileHEVCMain : VAEntrypointVLD
VAProfileJPEGBaseline : VAEntrypointVLD
VAProfileNone : VAEntrypointVideoProc


The terminal shows this when playing a video:
ATTENTION: default value of option mesa_glthread overridden by environment.
libva info: VA-API version 1.20.0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/radeonsi_drv_video.so
libva info: Found init function __vaDriverInit_1_20
libva info: va_openDriver() returns 0

Please help!