Bug recreate steps: Using LibreJS 7.20.2 in Firefox 91.0.2, and running on Ubuntu 18.04
1. Load a page that encounters a script problem. 2. Click on the " Complain to Site Owner" button. ===> Dialog opens (OK). In this case, the text "Could not guess any contact page for this site" is displayed (OK). 3. Click the X icon in the upper right corner, to close the dialog. ===> The dialog will not close. One must backpage in the browser or reload the page to get rid of the dialog.
