First of all, thank you very much for such a great idea and its realisation.
Unfortunately, I am facing a deal-breaking issue. While my Joplin is running, everything is OK and running perfectly. As soon as I close Joplin, or do not start it at all, every single search engine attempt pops up the error message posted by rxliuli about two posts back.
The plugin thinks that the webclipper service is not enabled, but the real reason it could not connect is that Joplin is (intentionally) not running at all.
I do not know if I am doing something wrong. There are times when I do not want to run Joplin but I still want to use Firefox to "google" things. Is there a way to fix this behaviour? I have not tested with the Chrome browser and plugin combination.