You mean that there are no bubbles in the cloud and it is only straight line segments? That usually happens when the cloud shape is set to Polygonal, but that is not the case on your screenshot.
Can you transfer the parameters of another Change Marker that works? Or delete it and recreate it?
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A colleague sussed it out. In the Issue Settings you can choose to only the current issue back to only a certain issue or only the current issue. The Change Markers that were "hiding" their polygon lines were from a previous issue and the Issue Settings were set to show only the current issue.
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