Sober but interesting add-on, specially when tabs are a lot Rated 4 out of 5 stars

Really basic functionality that should be built-in for sure!

Some suggestions please :
-Add a double click option for opening new tab at the left of all the tabs...
-Add a line in default context menu when it appears after clicking on standard newtab "+", or anything else that can remember the add-on is here!

Simple useful add-on for users with many open tabs Rated 4 out of 5 stars

Very handy if you tend to keep a lot of tabs open and occasionally want a new tab next to the current one.
Works fine for my use case (thanks Archaeopteryx), but doesn't seem to work properly if you have changed browser.tabs.insertRelatedAfterCurrent to false (see:

Options also allow setting (unmodified) left-click, should you want to change the default behavior (thus it's also a partial replacement for Tab Control add-on, which is no longer maintained).