I thought I would find what I was looking for with this add-on, but I did not. So I make the suggestion, if it can be added:

Protect main tab (with keyboard shortcut) so that it does not close, even if you click the middle mouse button. I use a software that makes mouse and keyboard gestures, and there are web pages that open additional tabs with viruses (especially link shorteners), the intention is that when I use the keyboard shortcut in automatic, it will close any page that opens to the right, and if it did not open any, it will not close the main tab.

ome time ago I used an add-on called: Tab Mix - Links, which did just that, but due to changes in Firefox it no longer has the functions it used to have. I hope it is understood, but thanks for developing this add-on.