Really useful extension, nothing to really complain about.
Simple, Light, Effective! I use it all the time

halved FF memory usage.

Saw a noticeable drop in the amount of memory my PC was using by about 20% after installing this add-on.

OK

Great addon, but have to revert back to the old version temporarily because the addon doesn't work at all, including not discarding any inactive tabs after x number of minutes after updating to v.0.6.2