Rather than hide, I'd have them "sink to the bottom" or add a "hidden page" with the opposite semantics (unhide on long press). This prevents mistakes and allow

Rather than hide, I'd have them "sink to the bottom" or add a "hidden page" with the opposite semantics (unhide on long press). This prevents mistakes and allows people to create a workflow where they only whitelist (or filter to top) certain emojis, while still having access to ones they didn't think they needed.