Yes- any shoulder bag seems to gets stopped for FJ. I even saw a woman with wristlets being told she had to put it in a locker. (It was tiny - like wallet on a string!) I only remember because she made a HUGE fuss when she saw me walk by with with a belly bag on. The TM explained that the harness would fit over my belly bag and since it was clipped around my waist I didn't have to hold onto it. I left before I heard how that one ended.
I have never had a problem with my purse on any WDW ride.
Also - heads up. At the bargain store on the way out of IOA they have small belly bags for $12.95. I swear it is the exact same one I bought for $15.95 at the regular store! (But I got my passholder discount so it was ok!

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