i see people talking about it not working with version this or that...but i don't think they are telling you everything.
"Double Click to Close/Open Tab" doesn't seem to work in SOME themes. mainly large, change everything type of themes.
example...it won't work with the theme "FT DeepDark v.11.2", but it works perfect with my "Noia 4 v.2.0.0" and all of it's add on options.
so i just use Noia and it works perfect every time. sorry about 4 stars though, but it does seem to have some theme based bug. nice work, and thank you for sharing.