Looks like Comfrey to me.

Yep! Very nice to have too. Good compress for strains and makes good plant food if soaked a few days in a bucket of water.

Spreads like mad and has no effect whatsoever on any strain, sprain or break despite its name.

Quite hard to dig up as the roots go quite deep once it gets established. It’s an attractive plant in the hedgerows but I wouldn’t allow even one in my garden. It’s a thug!

Can't agree there Owd - much used remedy at our house when I was a child. (Unless of course if was just the compress that did the trick!)