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Unfortunately, some of websites like YouTube, Twitter or Instagram do not allow website translation translation into website therefore you have experience the problem using website translation.
In this case you can use
Pop-Up Bubble Translator:
https://about.imtranslator.net/tutorials/presentations/imtranslator-translator-for-firefox/popup-bubble-application/
Inline translator:
https://about.imtranslator.net/tutorials/presentations/imtranslator-translator-for-firefox/firefox-inline-translator/
ImTranslator:
https://about.imtranslator.net/tutorials/presentations/imtranslator-translator-for-firefox/imtranslator-application/