After many weeks i found out this extension was causing CMD+UP and CMD+DOWN arrows to stop working to scroll up and down pages (HOME and END equivalent in macOS vs Windows.) Very annoying.
Yes it can be disabled in the settings, but it should not be enabled by default, hijacking basic Firefox shortcuts/functions.

Other than that it's a great addon.

OMGOMGOMG Finally the Opera 12 behavior I missed so much.

That is what I want.

Yes, as someone stated below, it's surprising that this addon is not popular anywhere, I just tried clicking 9-10-ish search pages before the short description caught my attention. It seems that the author did not update the addon regularly, but maybe because it has been working perfectly! :) I was sad that the author of Tab Mix Plus has not updated his addon for Quantum, but now I've found this nice addon which has the function I need!

Really useful if you work with many open tabs.

Stops Firefox from showing the last-opened tab after closing a tab.

This extension shows, instead, the last-viewed tab after closing a tab - which to my mind is more logical.

Thank you for providing one of the most important (for me) functions of Tab Mix Plus!

I'm still trying to find extensions to replace all the functionality I used in Tab Mix Plus now that it is no longer compatible with Firefox and this gets me part of the way there. Thanks for making this!

Perfect, thanks!