Yes, this was a problem. And now I have the same message as you had and the corresponded message in Joplin. Do not know why I didn't have this several hours ago.
This just started occurring in my Windows 10 installation. I haven't changed the Joplin install or the web-clipper install. I tried uninstalling web-clipper and re-installing but the problem persists.
There is no message about what permissions it is looking for. Joplin desktop seems to be running fine.
I updated to Joplin 2.1.7, I use the web clipper in Firefox, I get the permission message, I grant permission in Joplin (clicking on the "Grant permission" link). I use the web clipper in Firefox, I get the permission message. In Joplin, the message is there again. I click... ad infinitum. Running Joplin on Ubuntu 20.04. Even granting permission, I keep getting the permission message, no matter if I reload either Joplin or Firefox.
Joplin wanted to update from 2.1.7 to 2.1.8 on my computer. The warning about not installing this version if I use the web clipper is still present. I have not updated because I rely on the correctness of the warning.