When holding ctrl + Q and dropping all items out of your inventory, many of them vanish.
Dropping your entire inventory that way leaves about 13 stacks remaining, on the ground, while the other 23 vanish and don't reappear on reloading.
Tested in Minecraft 1.19.2 vanilla, creative.
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We're tracking this issue in MC-252651, so this ticket is being resolved and linked as a duplicate.
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