We just released the next version of Snooze Tabs - v1.0.16. Here's a detailed list of all the changes in GitHub. But, TL;DR, here are the highlights:
Deleting a snoozed tab now reveals an undo button. It's available for 5 seconds, or until you close the panel.
If the only window open is in Private Browsing Mode, Snooze Tabs will itself snooze and refrain from waking up any tabs until there is a non-private window available.
We're a little smarter about maintaining the backup folder of bookmarks. Hopefully it should cause fewer problems when using Snooze Tabs on multiple instances of Firefox using Sync.
Thank you for participating in the Snooze Tabs experiment! And thank you for participating in these forums. Your input & feedback are the reasons why we're here!