Should non-woven wallpaper be primed before painting?

Good day,

I have a question for the knowledgeable painters.

I would like to paint an orange non-woven wallpaper white. The planned color is Alpina white.

Do I need to prime the non-woven wallpaper beforehand or can I simply paint it directly? If yes, what kind of primer should be used? What could happen without priming?

Briefly about the wallpaper's texture: non-woven wallpaper with texture, no differently colored patterns or similar.

I look forward to your answers.

P.S. In another room, I want to re-wallpaper with woodchip non-woven wallpaper. Surely no primer is necessary on the wallpaper before painting here!?

The non-woven wallpaper does not need to be primed anymore. However, it may be necessary to paint twice for the white color to cover. To ensure this, I would apply the first coat diluted with water and then do the top coat. Paint corners and edges with a brush, then smooth out with a small roller. This prevents unsightly overlaps later because the brush absorbs more paint.

A consultation at a specialist retailer also helps here.

I myself have experienced that the substrate, the paint used, and the corresponding tools must harmonize if you want flawless results. If one parameter is off, the whole thing is doomed to fail. So maybe invest a little more money here as well.