1+
I used to have this feature as a bug - so I never thought it might be missing.
Until I used “Close all” once - now I am here with all others 
Give us an option to decide if
- left click in left pane opens as new tab or right in place
- and ctrl/cmd click opens in place or as new tab
I was so used to open as new tab, that I closed files without realizing, just by open files.