-Block websites from being visited. The parameters take an array of Match Patterns, as documented in https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Match_patterns. Only http/https addresses are supported at the moment. The arrays are limited to 1000 entries each.
+Block websites from being visited. The parameters take an array of Match Patterns, as documented in https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Match_patterns.
+The arrays are limited to 1000 entries each.
+
+As of Firefox 83 and Firefox ESR 78.5, file URLs are supported.