Register session for startup locally only

[retroj]

Is your feature request related to a problem? Please describe. I use Tab Session Manager to share sessions among multiple computers, with session information synced on Google Drive. On each computer, I would like to independently choose startup sessions. Typically I have a "main" session for each machine, and I want each machine to load and track its own main session on startup. I don't want startup registration to be synced between devices.

Describe the solution you'd like Some possible ways this could be implemented:

1. Change the default behavior of "Register for startup" to store the startup tag locally only. This would only be a good option if it were deemed that this would be the best default, which is not my place to say.
2. Add a menu item "Register for startup locally" to implement the idea. A new tag would be introduced, for example "startup-local" so that it wouldn't conflict with synced startup tags.
3. Add an option to the addon's preferences that determines the sync behavior regarding startup tags.

Maybe there are other ways of implementing it that a person more familiar with the code would see?

Many thanks for considering this feature. It would make it easier for me to keep all my sessions synced and organized in my workflow with Firefox and Tab Session Manager.