Button only selects the faces on the 3d viewport panel. https://cdn.discordapp.com/attachments/1514004304464445651/1514004305106178358/CylinderCapBug.mp4?ex=6a29c9e3&is=6a287863&hm=c24b83469881dc6e8017c3ee8f987feb5412dc5be969bce5e4950bcf38cd667e&

This bug is tied to changes in Blender 5.0, specifically when developers allowed working in Sync-on mode as independently as in sync-off. It’s already been fixed and will be available in the next release.