Incorrect AssemblyRootPart selection

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#1

I added 2 parts welded to each other, one of them is massless and the other one is not. According to the Roblox documentation Assemblies | Documentation - Roblox Creator Hub, the part that isn’t massless should become the AssemblyRootPart, and it does, until the massless part is connected to an anchored part with a hinge constraint, then the massless part becomes the AssemblyRootPart and gets forced to have mass because of that. However, the anchored part is a completely different assembly due to the connection not being rigid, and should have no effect on the AssemblyRootPart of another assembly.

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File with bug:
IncorrectRootPartSelectionBug.rbxl (53.5 KB)

#2

Instead of using a weld, can you try weld constraint? At the same time, we will look into this issue. Thanks!

#3

Thank you for looking into this! I tried using a WeldConstraint instead, but the massless part is still being selected as the root part. Also I forgot to mention, when I parent the attachment to the part with mass, it becomes the root part