Just tried it. I've been looking for this for a long time. Nobody seems to know about it. To update one users review, it does close the current tab now. I would like it to be added to "recommended" by Mozilla/Firefox, as I prefer all extensions to be, because I worry about what might or might not be gathering data.

Please, add translations, and button on toolbar.

Works well, but
the description is wrong. All tabs of the same domain are closed _except_ for the active tab - where you opened the dropdown menu with mouse-right-click in order to select "Close same domain tabs".

I will give 5 stars when that current tab is closed as well.