Based on the posts I’ve seen, I’d say it’s almost like a right of passage for a bun. Luna had it once before and I was in tears for hours! She’s fine now. The important thing is to catch it early, so recognizing the signs is key – not eating/drinking/pooping, lethargy, hunched position.

Not all buns get full GI stasis, which is when the intestines stop moving and there’s no poop. That’s a serious and life-threatening condition that warrants vet care.
Most buns will however get a little bit of tummy trouble at some point. Some get it when they are young and their GI microbiota still isn’t fully developed. Other buns get it from an inappropriate diet (and what’s inappropriate for one bun can be perfectly well tolerated by another, so there’s no real one-diet-fits-all, rabbits have individual differences as to what food agrees with them.)
Some buns get tummy trouble from stress, f ex when you move house or add another pet to the household.

I always keep baby gas drops (simethicone) at home and use it as first aid. It’s not absorbed by the body but acts locally in the intestines and comes out with the poop. There’s no hard scientific evidence of its effectiveness in bunnies, but it’s much used by bun owners and recommended by Medirabbit and dr Dana Krempels on suspicion of gas.

Another good thing to have at home is a fever thermometer and a hot water bottle – a poorly bun can get hypothermic and need warming up while you are waiting for your vet to open. (In case bun falls ill out of office hours, and that’s as a rule when all animals fall ill).

To prevent GI stasis, a diet that consists of lots and lots of grass hay is the best thing.

I never had to deal with GI stasis with my first bun. We had a bit of a scare with my current bun about 5 days after her spay, my vet doesn’t think it was true stasis but the combo of anesthesia, pain meds and limited exercise slowed down her gut. I keep a package of the apple banana flavored critical care in my freezer just in case, and I’m planning to pick up baby gas drops