Splintering is coming from the window reveal / window trim

Hello everyone,

We have now been living in our new building for a year. At our windows, this silver foil constantly comes through at the frame. I can cut it off with a cutter, but after a few weeks it is there again. We have this phenomenon at almost EVERY window.
We have wallpapered and painted everywhere. Does anyone have an idea what this could be???

Thanks in advance!

Could that be the sealing tape? We installed our windows ourselves and had to use a sealing tape that was attached with a special adhesive. For us, some of it also protruded, but I simply glued the protrusions into the reveal with the assembly adhesive, then plastered over them and painted. Why it keeps happening for you despite cutting it off is a mystery to me. I mean, that stuff basically doesn’t move. At least not in our case. I’m curious if anyone else has an idea. If in doubt, maybe have the window installer come over?