User Agent: Mozilla/5.0 (Windows NT 6.0; rv:48.0) Gecko/20100101 Firefox/48.0 Build ID: 20160706215822 Steps to reproduce: Installed Firefox v48 Actual results: Tabs are no longer separated into groups, although the group they belong to appears in the title bar Expected results: Tabs should have been separated into groups
We removed Tab Groups in Firefox 45. What release of Firefox did you upgrade from? Did you have other add-ons installed to recover tab group functionality? Without any such add-ons installed, you should have seen a migration page that let you restore tabs to separate windows. Consider using an add-on like https://addons.mozilla.org/en-US/firefox/addon/tab-groups-panorama/ to restore the feature. As it is, tab groups not working is not a bug in Firefox, it's expected, so I'm closing this report.