Your missing element is a guide layer [link], as indicated by the cyan hash marks over a gray field on the layer in the timeline panel.
Guide layers are visible in the comp viewer window, but do not render out to files or upstream to containing comps. There is a “Guide Layer” toggle in the right-click context menu for a layer or in the Layer menu.
Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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