What do these blue and orange boxes mean that appear when I select a brush in the brush presets window?
I believe I have figured it out. The orange and blue box's are inidcators of the type of brush you have selected. For instance a blue selection means you have an eraser brush selected. An orange box means you have a brush selected.
You could try alternative brush managers, like MagicSquire. It provides brush differentiation with small icons. E.g. an eraser would have a small eraser icon next to it. Just sayin'
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