Option to Always Reuse Active Tab
This is equivalent of Right-click, Open Link, which opens all links in the current tab, even if the link target is "New Window."
With this option enabled,
- Shift+Click would still open a link in a new tab
- Ctrl+Click and Middle-click would still open a link in a new background tab
- Right-click menu items would function as normal
- Mouse gestures would function however they are defined
- Left-click on link would always open the link in the active tab
This can be achieved with a script. It might not be a perfect solution, but it's better than nothing.