**Compatibility:** Firefox 60, Firefox ESR 60\
**CCK2 Equivalent:** `permissions.install`\
**Compatibility:** Firefox 60, Firefox ESR 60\
**CCK2 Equivalent:** `permissions.install`\
signon. (Firefox 83, Firefox ESR 78.5)
spellchecker. (Firefox 84, Firefox ESR 78.6)
toolkit.legacyUserProfileCustomizations.stylesheets (Firefox 95, Firefox ESR 91.4)
signon. (Firefox 83, Firefox ESR 78.5)
spellchecker. (Firefox 84, Firefox ESR 78.6)
toolkit.legacyUserProfileCustomizations.stylesheets (Firefox 95, Firefox ESR 91.4)