I'm planning to hang vinyl, prepasted, strippable wallpaper trim (7") at
the top of the painted (satin or eggshell finish)walls. Even though the
trim comes prepasted, should I use extra adhesive, due to the higher
humidity generally found in bathrooms especially around the tub/shower
combo?

The bathroom has a window, but no exhaust fan. Its perimeter is 42 feet.

The instructions don't mention anything about high-humidity rooms. They
just recommend an oil-based or wallpaper primer first; I'll use the latter.

Thanks,

Ray