Tested with Firefox on safe mode / no addons. Win 7. FF 59.0.1 (64-bit). Have noticed this for the past month or so. User is presented with a blank/white screen on all forum pages. Apparently this effects all discourse sites for users that have
dom.webnotifications.enabled = false
in about.config. This is not an uncommon setting, it would be great if this could be fixed so that having notifications disabled won’t render block the entire site.