Bathroom ceiling bubbles

Joe F

I repainted the ceiling in my master bath about a year ago. The old paint was adhered well, but I went over it with Zinser primer and top-coated with Duron semi-gloss. I'm now seeing some bubbles in the paint, primarily in the area directly over the shower stall. The bathroom has a good fan that works well.

What are the right prep steps and products to permanently fix this issue?

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dytecture

Is the Duron paint suitable for bathroom with high moisture content? Otherwise you`ll have to scrap off the bubbles and re-prime the ceiling.