I did some digging around in the machine code. When you attempt to set a clip marker property via script (in this case name) it calls SL::MarkerLiveObject::SetName which then calls MZ::ExecuteActionWithoutUndo. There's a check in MZ::ExecuteActionWithoutUndo check to see if the first param is empty. Which in my test it was, so MZ::ExecuteActionWithoutUndo bails and the proper chain of events never makes it to BE::Marker::SetName. To verify this behaviour, when you modify a clip marker name in app, MZ::ExecuteAction gets called (it contains a similar check as MZ::ExecuteActionWithoutUndo) and the first param check passes and eventually makes its way to passing the value to BE::Marker::SetName. Hope this helps to solve this issue quicker.
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