Complexity of test scenarios. There were already ~6 user states on ~20 supported operating systems with ~10 add-on types. There has already been public announcement of a solution for older versions of Firefox without studies including a manual install option.
> For users who cannot update to the latest version of Firefox or Firefox ESR, we plan to distribute an update that automatically applies the fix to versions 52 through 60. This fix will also be available as a user-installable extension. - https://blog.mozilla.org/addons/2019/05/02/add-on-policy-and...
> For users who cannot update to the latest version of Firefox or Firefox ESR, we plan to distribute an update that automatically applies the fix to versions 52 through 60. This fix will also be available as a user-installable extension. - https://blog.mozilla.org/addons/2019/05/02/add-on-policy-and...