Since some months I'm developing restartless versions of my Add-on (2.x) with the Add-on SDK. All versions before 2.x were developed without SDK. Sadly there is still a significant amount of users that have installed 1.x versions (because of old Firefox versions). The complete code base together with the Add-on concept was rewritten for 2.x versions and is not backward compatible.
Here is my question: What is good practice for publishing one final bugfix version for the 1.x Add-on users? For me it's most important not to mess my 2.x branch with that bugfix version - it only addresses "outdated" users. Next to some last bugfixes I want to communicate that 1.x is no longer developed and want to encurage 1.x users to do an browser update.
My idea would be to publish a 1.x version (e.g. when last version was 1.7 I would publish 1.8) with a Firefox version range from 1.5 to 8.0. But I'm not sure if this has any bad influence on my 2.x branch/users, if this is possible at all or if there is a better way.