That's why I wear a protective mask before cutting them:
Anti Meme
We're the anti-meme community where the joke is that there isn't one, and by explaining that, we've ruined the whole thing, but we all find the collective misery hilarious.
The music of comedy is more important than the joke itself.
Follow the instance rules please, this is a lovely instance.
Chopping onions with my glasses on results in a smaller amount of tears and eye stinging than with my glasses off. So unironically this. Glasses acting as a tiny localized facemask/makeshift eye protection.

How dare you, you killed that poor Onion. Onion has family, how dare you!!
question, can people be immune? that never affected me, regardless of how many onions I chop? I know it's unlikely, because it's basically making sulfuric acid in your eyeballs
Contacts do prevent the burning. I never even noticed the difference until someone told me about it, but sure enough, I can distinctly remember never crying once I switched from glasses to contacts.
There is a theory that a sharp knife will help you not cry, a dull knife tears the onion more and releases more sulfuric acid, a sharp knife just cuts with less tearing so there is less making you tear up.
good theory, but last month I cooked with friend, was chopping onions, lots of them, it's a small kitchen not very well ventilated. everyone had to leave with tears, with me not feeling barely anything.