Recently Mozilla team launched firefox 10. Apart from bug fixes and other improvements, one improvement that browser launched was Add-On Compatible. Previously, everytime a new version was launched, some add-ons were not "ready-to-use" until developer makes them ready for that launched version.
I thought this behavior was changed in version 10, with all add-ons maintaining reverse compatibility.
Did I misunderstand this feature, or is something else going on?