Translate any selected text into the language you wants with google translator
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I'm sorry, I didn't encounter the problems at docs.google.com just like as what you said. If add the docs.google.com to the excluding list will fix your problem, you can open the script what you downloaded and add it by your own.
On my last post I forgot to mention :
Browser - Pale Moon 28.17 (32 bit)
Win 7 x64
gstt ver. 4.10
Issues with Google Docs - ctrl-c, ctrl-c & ctrl-v in google docs editor stops working when the script is enabled.
Can you please fix it or add docs.google.com to the script's "built-in" @excluded lines?
In the meantime I added docs.google.com to the script excluding list.