It does exactly what I want it to do - open new tabs or duplicate tabs at the far right rather than next to the open tab I'm in. Thank you very much!

jestem zadowolony

"Activate left after close" doesn't work at all.
"Open new to the right" works unreliably.

Working solution is combination of "Open Tabs Next to Current" and "Select After Closing Current".
Though using 2 extensions to cover basic tabs customization is ridiculous, of course... :(

設定After close, Change to left Tab不起作用.書簽欄一次打開多個分頁.順序會顛倒
Set After close, Change to left Tab does not work. Bookmarks bar opens multiple tabs at once. The order is reversed.

Doesn't seem to work. Set it to open new tabs last but it doesn't.

GOOD!
Is it possible to add a option as "After Close Tab, Chage to last unread tab of source tab"?

Cool! It works! I prefer Open -> Right, Close -> Left and it does! I hate the default! Thanks!

outstanding ! exactly what I wanted :-D

dont realy work!

I'm using this in conjunction with the 'Tree Style Tab' extension because that one adds some new tab behavior and not all the options to change it to my liking. Hence some other extension was needed that got me back the functionality I had with 'Tab Mix Plus' in versions <=56 of the browser (After Close, Change to Last Active Tab). It also does not appear to interfere with the grouped tree behavior when opening tabs. All in all, I'm happy with it.

Edit: if there was one thing to criticize then it's to make the extension page on AMO more user-friendly. Add a more detailed description, maybe create a graphic/modified screenshot to illustrate the changes that are possible. I don't need any of this, but for the average user it would undoubtedly help

It simply allows me to open and close tabs the way I like them. For me it's open link to tab at right and upon close to referring tab or last open one.

Simple and gives me control over the most annoying default tab behaviors so they work within my workflow. If you would add undo last closed tab it would be perfect.

Спасибо!!!

Thank you so much for the BTW tips!!

It works sometimes, but it’s too inconsistent for my needs.
So I’ll keep waiting for an update to TMP.

Very much would do what I was looking for - unfortunately I have to agree with the previous comment that it works very inconsistently.

There are some cases where it works as expected, but especially for tab activation after closing a tab it is really un-predictable where it jumps to ... especially if you have been changing tabs in between.

In some cases also opening the tab (I have set it to right) does not work but opens at the end ...

I hope that this will be updated and improved as I could not find any other add-on providing this functionality (still hoping for TabPlus one day :-) ).

PS: I do not know / understand what the author wants to indictate with those lines:
btw:
about:config -> browser.tabs.insertRelatedAfterCurrent -> true
about:config -> browser.tabs.selectOwnerOnClose -> true
Would that indicate that this setting is needed for the add-on to work correctly (it does not), or are those settings changed by the add-on? Some more information might be helpful to improve that add-on ....

PS: Unfortunately the author does not seem to respond to the issues and there has been no update for adressing them ...