The big question being: what is recycled filament? What was the previous usage of that plastic? Could it be enough to just add like a few percent of the in plant waste (stuff that gets removed from machines between batches for example) to new pellets to call it recycling. I expect 90% of what’s sold as recycling filament to be such a greenwashed product. I sincerely hope it’s bot the case but I’m sceptic.

Just don’t run broken software. The attackers will not be able to exploit you then. If they have zero day exploits, the WAF will most of the time not save you since they are often pretty easy to circumvent. WAFs are only effective against old and shitty exploits that should be patched anyways since ages.

Wafs don’t make you safer but create unnecessary attack surface. Just keep your machine and services up to date.