Not as pretty as SnoozeTabs - but it doesn't abuse Permissions, so I chose this one.

One problem I have with this addon is that re-opened tabs open "together" with your current tab (like they're shadowing your current tab). So imagine: you're reading some (longer) website, in background 5 other tabs opened from snooze. But they're "connected" to your current tab - if you close current tab (Ctrl+W) it will also close those 5 tabs as well. If you then bring back your tab from oblivion (Shift+Ctrl+T) - it will reopen those 5 snoozed tabs as well. Very, very inconvenient behavious - SnoozeTabs is much better here.

If this is fixed - I will upgrade the score to 4, perhaps even 5.

[update Oct 2020] Unfortunately I need to downgrade it to 1.
Developer doesn't read comments (no care, then - suggested fixes were not even addressed), and in recent Firefox (82) half of the snoozed windows don't even open - they simply disappear.
Unacceptable.

Avoid.
Stick to something that is being kept under development.