When Firefox Sync is enabled it will create a Sage Feeds folder on every machine that uses Firefox, even on those where Sage is not yet installed. That's OK but it means that when Sage is installed for the first time on one of the other machines it should check for the existence of this folder before creating it. The Sage installer apparently does not do this, because it created a second Sage Feeds folder which I had to delete. After deleting the duplicate folder I found that the newly installed Sage had lost its sense of where the feeds folder is located. I fixed that by manually configuring Sage to point to the existing Sage Feeds folder.
Yes, we should be doing a much better job accommodating Firefox Sync. Sage tracks its feed folder using a custom Places annotation, which unfortunately doesn't get synced. I'll look into a short term workaround.
When Firefox Sync is enabled it will create a Sage Feeds folder on every machine that uses Firefox, even on those where Sage is not yet installed. That's OK but it means that when Sage is installed for the first time on one of the other machines it should check for the existence of this folder before creating it. The Sage installer apparently does not do this, because it created a second Sage Feeds folder which I had to delete. After deleting the duplicate folder I found that the newly installed Sage had lost its sense of where the feeds folder is located. I fixed that by manually configuring Sage to point to the existing Sage Feeds folder.