Hello, In various linux distros such as LinuxMint (18.3) and Trisquel (8,0), the Firefox (?) and derivatives, such as IceCat (52.6.0) exhibit a condition whereas:
When the 'remove all sites' option under "Warn me when sites try to install add-ons" "Exceptions", is chosen, https://addons.mozilla.org and https://testpilot.firefox.com (which are there by default) return under "Exceptions" when the browser is restarted. (Aside: Seamonkey's 'exceptions under 'permissions' are at least able to accept 'block' option in the "Data Manager".) Thanks.
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