When you’re editing a group game (Cloud Edit or regularly) and create a LinkedSource by rightclicking a script and selecting “Create new LinkedSource”, the asset is uploaded under your account. It seems as if studio doesn’t append &groupId=GROUP_ID to the Upload.ashx url when editing a group game, even though it should.
When you use a LinkedSource in a group game that’s not owned by the group, only the real owner can edit (or even open) the script. In an online game, the LinkedSource won’t load, as the group doesn’t have access to it.
I manually uploaded a script using Upload.ashx with &groupId, and it got created under the group just fine, so it’s just studio that doesn’t use that parameter when it should