I have seen LOL on French forums and once asked if they know what it means. I think Frenchie replied saying they know the meaning of it, without maybe knowing the words.
They have "mdr", which I think is mort de rire.
Hope a real virtual French person may clarifiy more.
Animal Aid Saint Aubin
"Saving the life of one animal may not change the world, but the world will surely change for that one animal"