I recall reading that the drop shadow in the ArcMap layout view had some significance (whether some parameter was set or not), but I cannot recall the meaning. Image shows the area I am asking about.
I am not sure what you mean about significance, except for aesthetics or personal preference... to provide the sense of depth to an output
it is an element of the frame
I'm note sure it this really has effect on exported or printed results (I haven't tried though).Since the drop shadow shows its effect outside the page, I don't think it is considered in the export or print. You can change the drop shadow settings of your map frame/data frame and when the frame does not occupy the entire page, you will see that in the exported and printed results.
In this old blog Figure-ground: Drop shadow | ArcGIS Blog they mention drop shadows used for geographic features (which is different).
There is a thing with transparencies that would rasterize all the layer below it.
Thank you, but I am not talking about drop shadows that I would add as a user for aesthetic purposes. I am referring to the the overall layout page's drop shadow that ArcGIS adds. I just figured it out myself (somehow posting makes me realize the answer, this has happened before :-)). It's the Print setting. See attached. If it's selected to Use printer paper setting, you get the drop shadow. If unclicked, no shadow.
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