Ctrl + Shift + C Should Copy
Intercepts Ctrl+Shift+C, blocks opening developer tools, and copies the selection to the clipboard.
What is Ctrl + Shift + C Should Copy?
Stats
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Other platforms
Summary
Injects a script into pages to intercept Ctrl+Shift+C as a copy command, not allowing it to open Developer Tools.
Concerned about permissions? There is no convenient way at the moment to have Firefox run this extension on every site without "all sites" permission. However, you can look at what the script does, it's minimal. https://github.com/jscher2000/Ctrl-Shift-C-Should-Copy/blob/main/content.js
You also can use an online extension reader to extract the files for review. For example: https://robwu.nl/crxviewer/?crx=https%3A%2F%2Faddons.mozilla.org%2Fen-US%2Ffirefox%2Faddon%2Fctrl-shift-c-should-copy%2F
If you use Greasemonkey, Tampermonkey, Violentmonkey, or FireMonkey, you also could consider using the above file in a user script.
Icon from https://www.iconsdb.com/blue-icons/copy-icon.html.
User reviews
Safety
Risk impact
Ctrl + Shift + C Should Copy may not be safe to use and it requires some risky permissions. Exercise caution when installing this add-on. Review carefully before installing.
Risk likelihood
Ctrl + Shift + C Should Copy has earned a fairly good reputation and likely can be trusted.