Reproducible on: Firefox 40.0a2 and Firefox 41.0a1 across all platforms STR 1.Launch Firefox with clean profile. 2.Install an older version of a signed add-on. 3.Navigate to about:addons. 4.Select Extensions from the left menu. 5.Click on “More” link that correspond to the installed add-on. 6.On Automatic Updates section, check “Off” radio button. 7.Click on “Check for updates” link which appears near “Off” radio button. 8.Click on Available Updates that appears in left menu. ER The elements are correctly aligned. AR The elements are disorderly displayed. Additional notes: - This issue is reproducible on Firefox 40.0a2 (2015-06-19/22) and Firefox 41.0a1 (2015-06-21) under Windows 7 64-bit, Ubuntu 14.04 32-bit and Mac OS X 10.9.5 - This issue is not reproducible on Firefox 39 Beta 7 (20150618135210) - I am attaching a screenshot: http://i.imgur.com/wqRLl6a.jpg

Per policy at https://wiki.mozilla.org/Bug_Triage/Projects/Bug_Handling/Bug_Husbandry#Inactive_Bugs. If this bug is not an enhancement request or a bug not present in a supported release of Firefox, then it may be reopened.