I find the marching ants distracting when working on a document. For example: isolating an clearly-defined area so that the rest isn't affected by brush strokes. I find that having the marching ants around screws with my value and color perception. A workaround is to make a completely-transparent mask selection. However, this seems more like a hack and it's better to have a completely separate option for toggling selection display. Reproducible: Always
Thanks for the report! You should be able to toggle the marching ants by clicking "Display Selection" in the Select menu, or, if you are using the default keyboard shortcuts, by pressing Control + H.
Nicholas is correct, this feature already exists, so let's close this report.