I live in a really dry climate, so I don’t really notice issues unless I have a spool out on the printer for months, and even then dust is more of an issue than humidity.

To be safe, I bought a storage bin with a gasket on the lid that I store all of my other spools in, and that has seemed to work great.

I saw someone else also suggest it, you could do an automatic fire extinguisher.

This one dispenses after 3-5 seconds of direct flame contact, others will be different.

Keep in mind that the sub count you see is the number of subscribers from your instance. I see 9.3k from my lemmy.world account, 250ish from my lemmy.ml account, and 300ish from my lemm.ee account.

Not sure how/where OP sees 12k though.