Thanks guys.

I started some investigations according to your advice, and buying this kind of filter screens seems a bit difficult as a particular individual.
My most "convincing" result was on Aliexpress:
I found only tiny 50x50mm (2"x2") sheets on the site, but I asked the seller, and he can provide larger ones, for example 100x150mm for 33.75$ (still very small), or 200x150 for 67.5$ (a bit expensive). At least, delivery time from China wouldn't be a problem here

But another stupid question: wouldn't welding glass a solution, as it is meant to both block UV and drastically decrease blue light (light emitted when welding is around 440nm)?
Of course, it wouldn't be perfect:
- very few light transmittance for passive glass, depending on the class, or
- even less transmittance for electronic glass, at least when on (black screen when the peachy is on, providing the peachy laser beam can activate the sensor), but better when off (controlling the print may still be possible with regular pauses during the process?)...