@zzzmeowzzz I was thinking about the Disable Automatic Translation option. It doesn't work?

For spell check or the user interface? Is there something wrong with adding Hebrew in Opera's settings? Goto the URL opera://settings/languages and click on "Add languages". Hebrew is in there and available for spellcheck after you add the Hebrew language.

I do not use ubuntu or gnome (or unity, if the screenshot is from 16.04 or older).
All the opera's .desktop file mentions is 2 entries that are only available under unity: one for launching it as usual and one for launching it in private mode, so I assume the other 5 come from gnome or from some gnome extension.

However, since opera is closed source, there is no ppa for it, you won't find anything to translate it yourself.

@patmat when i click that italian link it gets changed to uk
but i notice the site has a selector at bottom of page try that maybe

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