Rated 5 out of 5 stars

it does not work on Firefox 57. I had to install Copy On Select https://addons.mozilla.org/en-GB/firefox/addon/copy-on-select/
But, thanks for your efforts. It used to work great and I hope you will fix it because I am worried about one of the permissions of Copy On Select: "Access your data for all websites". So, 5 stars for the good work when it worked.

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