The wall should be painted prior to putting up wallpaper, I see people trying to put wallpaper onto unpainted drywall all the time! doesn't workNot that we can see.
I ripped a lot of the paper off yesterday and the wall underneath is pristine. It feels like either a wallpaper glue failure or that pristine wall is coated with teflon.
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And then there is the 'drying out' effect... ugh....