Not sure when this issue started happening but on 2019.3.0f1 it appears that Hinge Joint 2D is broken. I click the Edit Joint Angular Limits button and the handles do not appear
Can you please check if it works in older Unity releases than 2019.3, to figure out whether this is related to the current beta version. If it works in Unity 2019.2 for example, but stops working in Unity 2019.3, then you probably found a regression.
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