As a collaborator on a team created experience, I am able to rearrange thumbnails, upload thumbnails, but I cannot delete thumbnails (even those uploaded by me). This is very inconvenient as we upload many thumbnails to A/B test and I must request the game owner to delete them instead.
Page URL: https://create.roblox.com/dashboard/creations/experiences/63951305/places/137877687/thumbnails