@leocg Thank you

@leocg ok ill try. thank you for your answers

@leocg im dont try vivaldi browser. no, i have win 10 pro N

@leocg yup,
in google chrome all video works fine.

@leocg i try to turn off the extentions, the deffender and i reset opera settings. sadly still the same problem. not on just some youtube videos also in all facebook videos they sad to me "Sorry, we're having trouble playing this video". then i tried to install opera and still the same.

when play some videos not all youtube say to me your browser cant play this video. but google chrome run it normally. i need solution plz