That should have read, “under the tab with the circle & square icon”
The Text Editor Object will reflect the color changes made in the Appearance panel. Once a color is set you can see it if you change the Fill and Stroke setting in the same panel. Setting the Fill to Solid will cause the background to assume that color and setting the Stroke to solid will cause the outline box to assume that color. Text is not affected by these color choices. The color is maintained after going to data mode and back again. I can only guess that when you returned to graphics mode you did not re-select the object again and you got the default blue color box shown when nothing is selected.
My problem was I hadn’t set the stroke to solid. Still learning all about properties.
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