problem web browser

Hello,

I’ve a problem with your extension.
I do not understand, the extension only works on the browser on which I set it (in WPadmin).
Ex: If I change the text of a button under Chrome, this change will only appear on Chrome (not on Safari, neither on Firefox, nor on Opera.). But if I make this modification on Opera, there it only works on Opera … !!!
Can you help me ?
And is there a French version?

Thank you

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