Comment # 2 on bug 1199210 from Paul Hands

(In reply to Wolfgang Rosenauer from comment #1)
> For me everything still works as always with TW and FF100.
> 
> The difference might be that I still have the packman libavcodec installed
> which supports everything.
> 
> I heard that some people of openSUSE/SUSE worked on getting H.264 support
> through openh264 but nobody ever talked to me as Firefox maintainer if there
> is anything I need to take care of.
> 
> I currently have
> libavcodec58_134-4.4.1-10.6.x86_64
> libavcodec57-3.4.9-1.28.x86_64
> from Packman's Essentials installed and it's working fine.
> 
> What is installed for you?
> ls -l /usr/lib64/libavcodec*

I seem to have an assortment....

#yum list installed|grep -i libavcodec
ffmpeg-4-libavcodec-devel.x86_64                   4.4.1-10.6                  
                @System
libavcodec56.x86_64                                2.8.18-1.25                 
                @System
libavcodec57.x86_64                                3.4.9-1.28                  
                @System
libavcodec58_134.x86_64                            4.4.1-10.6                  
                @System
libavcodec59.x86_64                                5.0.1-16.3                  
                @System


And they all come from the @system repo.
or, to use your ls command...

# ls -l /usr/lib64/libavcodec*
lrwxrwxrwx 1 root root       24 Apr 30 05:33 /usr/lib64/libavcodec.so ->
libavcodec.so.58.134.100
lrwxrwxrwx 1 root root       23 Apr 11 23:52 /usr/lib64/libavcodec.so.56 ->
libavcodec.so.56.60.100
-rwxr-xr-x 1 root root  9829248 Apr 11 23:53 /usr/lib64/libavcodec.so.56.60.100
lrwxrwxrwx 1 root root       24 Apr 30 05:27 /usr/lib64/libavcodec.so.57 ->
libavcodec.so.57.107.100
-rwxr-xr-x 1 root root 11311712 Apr 30 05:27
/usr/lib64/libavcodec.so.57.107.100
lrwxrwxrwx 1 root root       24 Apr 30 05:33 /usr/lib64/libavcodec.so.58 ->
libavcodec.so.58.134.100
lrwxrwxrwx 1 root root       24 Apr 30 05:33 /usr/lib64/libavcodec.so.58.134 ->
libavcodec.so.58.134.100
-rwxr-xr-x 1 root root 12372264 Apr 30 05:33
/usr/lib64/libavcodec.so.58.134.100
lrwxrwxrwx 1 root root       23 Apr 30 07:16 /usr/lib64/libavcodec.so.59 ->
libavcodec.so.59.18.100
-rwxr-xr-x 1 root root  5264704 Apr 30 07:16 /usr/lib64/libavcodec.so.59.18.100


I could try switching to the packman packages, but I've had tht break lots of
stuff in the past....