sudo apt-mark hold chromium-codecs-ffmpeg-extra

And npin it when opera stable reaches 62 like so

sudo apt-mark unhold chromium-codecs-ffmpeg-extra

https://launchpad.net/ubuntu/xenial/amd64/chromium-codecs-ffmpeg-extra/73.0.3683.75-0ubuntu0.16.04.1

@maydin95
Actually, the opposite is more likely to happen. Configurations from a newer version of chromium (or a chromium based browser) is more likely to be incompatible with the older one.

Copying opera's stabel configuration file to opera's beta one may help.

cd .config/
rm -r opera-beta/
cp -r opera/ opera-beta/

Removing the opera-beta folder will result to losing ALL configuration made to opera beta.

Also moving (= renaming) the opera file in there from "opera" to "opera-beta" will work, but you will lose all opera and opera-beta settings, in case you want to keep them both
Symlinking it will also work, but do not blame me for any side effects.

Needless to say that all the above must done with opera and opera-beta NOT running.

I am pretty sure Opera will cry for non-existent setting parameters inside old config, so I wont try

But thanks for help, I knew this problem for literally years and I just figure out after this topic even though I asked before.

Thanks again.

HTML5 Proprietary Media on Linux

"... start Vivaldi from a Terminal using the command 'vivaldi'. The output printed on the terminal will include steps on how to install a support file. The output provided will be tailored to the version of Vivaldi you run, and take into account your distribution and architecture."

Also here is a page with test videos, which explains the h.264 problem :

HTML5 Video Test Page

Also moving (= renaming) the opera file folder in there from "opera" to "opera-beta" will work

Small typo.

cd .config/
rm -r opera-beta/
cp -r opera/ opera-beta/

Removing the opera-beta folder will result to losing ALL configuration made to opera beta.

Also moving (= renaming) the opera file in there from "opera" to "opera-beta" will work, but you will lose all opera and opera-beta settings, in case you want to keep them both
Symlinking it will also work, but do not blame me for any side effects.

Needless to say that all the above must done with opera and opera-beta NOT running.

Btw, I have a feeling that opera stable will jump from 60 straight to 62, as it did last time and jumped from 58 to 60, in order to keep up with chromium's upstream development.

Ubuntu 18.04.2 LTS (x86_64; XFCE)
Opera 60.0.3255.170
Chrome 73.0.3683.103

Yes. I'm using Linux Mint, and Update Manager just yesterday offered a Chromium codecs upgrade to version 75.0.3770.90. Opera stable is that far behind.

In other threads, people have said that the snap package of Opera stable does not have this problem. Another option might be to use a version of Opera beta that matches your OS's Chromium codecs. The latest Opera beta is 62.0.3331.14, and has Chromium 75.0.3770.80.

Another option -- if it's alright to mention Vivaldi here. They have the same problem. Their browser uses your OS's h.264 codecs. If there's a mismatch, no h.264 videos. But they have a built-in fix : open the terminal, type vivaldi, and it figures out what to do. It then provides you with a long command-line thing that you copy and paste into the terminal window, it fetches the right codecs, installs them, and then you have the h.264 videos. I wish Opera would have something like that.

Ran the latest stable update, now no videos play on youtube.

And as with the above poster, chromium ffmeg codecs are installed but version 75.0.3770.90 so cannot downgrade to version 73

Also I break my package system while trying to install glibc and cannot even change Opera version

I don't know, this stupid thing always happens and still no solution. If there is no codecs then Opera shouldn't update itself, or at least inform that my Ubuntu doesn't have codecs.