Right - I'm finding that this behavior (or something related to identification) makes it finnicky to update title/tags, and changes I make in the browser don't always seem to apply, even after resetting the connection.
If I edit a URL, stashmarks doesn't reflect the change in the UI, at least when the original is still pending download. Looks like it's actually changed internally.
Also, I can't delete (or edit) a bookmark in stashmarks that I no longer have saved in my browser. Recreating it and deleting that does nothing, even when logged out and then in.
Hope these critiques are helpful.
Clearly, these are all edge cases, and overall your service is impressive.