Remove the Reset button.

[bfabio]

Pressing the reset button is the most destructive action the user can take but, despite that

• the expected result when pressed is not clear (clear all the fields in the current tab? Remove the current tab? Clear all the tabs? Remove all the tabs?)
• it doesn't ask for confirmation
• it's incredibly prominent (right next to the most used button)

Removing the language tabs can still be achieved more intuitively by pressing the tab's close button.