Puntuado con 5 de 5 estrellas

Very useful, many thanks!

It would be great if in addition to the button you could also use a keystroke, for example the letter "H" to activate the function.

Esta valoración es de una versión anterior del complemento (5.1). 

With the key combination Ctrl + Alt + F5 you call the function of the button (the function depends on the options). Simpler keyboard shortcuts are already used by Thunderbird itself.