View > Patcher Inspector > Background color (choose from the palette)

you can also put the panel (and any other objects you want stabilized) into the Background, then choose View-->Lock Background. Now they won't be editable or selectable unless you choose Unlock Background.

Yeah, or use a bgcolor object, or if you did want to use panels, you can add them to the background layer and lock the background.

THANKS GUYS!

do you know how to make it so that every comment box in the patch as the same settings?

like background colour, font, and font colour?

just make one that you like and duplicate it (alt or option-drag). Or if you have lots already, select them all and use the Inspector, it will change them all at once. Same with any group of objects of the same type, and partially true with multiple types of objects (only the shared attributes will be available in the Inspector).

or if you have lots and lots and selecting them all would be too much, you can try [universal] . . .