Hans
I have a variegated form, and another in which the flowers looks like popcorn.
I think the variegated is Convalaria m. albostriata, and with flowers resembling popcorn, Convalaria m. prolificans.
The variegated, I can see now, the double is barely up from the earth. It grows together with the usual, and one with pink flower, so it must flower before I know which is which.
If you are interested I can send some roots to you.