Around the internal edge of the case lid there is an adhesive strip with a metallic backing. This can lift slightly or (more often) is affixed slightly out-of-line during manufacture causing it to buckle. Given the proximity of the vent it can then lift further and become visible or even protrude from the case.
Warranty can fix it or if you want to avoid that faff the lid can be removed and the seal can be massaged back into alignment with relative ease.