Plain Text Linker от Marnes

This addon won't be maintained further. I'm shelving this project due to lack of interest/utility and too much burden. The addon will remain available for download as long as the store allows, and the source on gitlab will also remain available to fork.
I do have a greasyfork account you can check out, and you can get new versions of CSL, DID, and IBCP there!

Available for Chrome too.

Functionality
When you double-click on a piece of plain text, Plain Text Linker tries to determine if what you clicked could be a URL and tries to open it. Try it!

Usage notes

• there's an option to require shift-doubleclick for a link to be opened, so you can still doubleclick URLs without anything happening
• you can choose if links should open in the foreground or background by default, and holding the Ctrl key will invert this behavior

The Options screen will automatically open after add-on updates if they force a change to any of your settings.

Please rate/review/donate! :)
A lot of time and work goes into creating my addons, and making changes or troubleshooting issues for users.

Problem, bug, broken, question, request?
Per Mozilla policy, only an evaluation of an addon's entire function with reasonable expectations is a proper review. Vague complaints or 1-star ratings for single reasons are considered spam, as are false claims about the addon not working at all. For more detailed discussions, use the linked support site or email.