I posted about a month ago about wallpaper over brown (unfinished) original plaster…. It’s going pretty well and the wallpaper’s almost fully murdered. It has taken some serious doing. Folks suggested I seal the walls with Gardz before skim coating, but I can’t get Gardz here - and I’m not sure if it’s right if I’m going over wallpaper residue and what is basically like masonry (it’s soooo thirsty, this wall). I would love to avoid fumes, as the home is occupied. Any suggestions? I’ve got an aubuchon and a SW store nearby.