For more detailed cases i can put links of videos that don't want or screenshot.

https://twitter.com/i/status/1630986553978920961 picked this random one but the same happen for all
Translation : Media couldn't be played

https://www.neko-sama.fr all videos don't work, same error message for all videos

https://www.xvideos.com/video75245581/une_fille_coreenne_prend_un_triple_creampie_pendant_les_rapports_sexuels_avec_un_abonne
I just tested this one to see if it was the same for pornsites and like i would have guessed it doesn't work. I obviously won't screen this one.
https://www.reddit.com/r/france/comments/11g2629/petit_olivier_gréviste_et_bloqueur_dhôpitaux/ same for this one

@leocg All YouTube videos work, Twitter videos don't, some videos on news websites work were others don't, the same for Reddit videos and streaming websites doesn't work either. I used html5test to see what codecs were supported and i found out that for some reason H.264, H.265 and MPEG4 ASP codecs weren't supported. Audio codecs have a problem too, AAC and Dolby isn't supported. I saw this after finding out that Spotify didn't work either.

I really don't know why it would do this right after i updated Opera. It's not what caused the problem because i tried to install an older version and it was still the same. I also repaired windows with scannow, DISM and chkdsk commands but the problem didn't go away.

@leocg yes video works on vivaldi, only Opera and OperaGX don't work,i have windows home. I did try to install the packages for windows N versions but it tells me that I didn't needed it because of my actual version of windows

So I run into this problem 3 days ago : videos on certain website doesn't work at all despite trying the basics like updating, restarting, reinstalling Opera... Either the video show me an error code or saying that the video wasn't found in the host servers. But i have no problems with Chrome or Edge reading any videos. The only thing i did between the moment where i had no problem and the moment where it started was updating Opera to it's last version.
Anyone know what could the problem be ? Or is it the last update that mess with Opera files ?

PS : I searched lots of solutions online but none of them worked + my computer is totally up to date either windows or my drivers.