I have the same issue.
Web Clipper: 7.15.1
Firefox: 93.0
MacOS: 11.6
When I click on the web clipper icon I see a window "You logged in Web Clipper" and the window infinitly open and close.
Having the same issue. Search and preview works, but notes are blank. Restarting the app works, but it's annoying
MacOS 11.1 Big Sur
v 10.5.7 build 2171 public
Editor: v114.1.14753
Service: v1.25.2