Aliasing blue_marking → blue_markings
Link to alias

Reason:

Also as a contingency:

red_marking -> red_markings
green_marking -> green_markings
black_marking -> black_markings
white_marking -> white_markings
purple_marking -> purple_markings
pink_marking -> pink_markings
orange_marking -> orange_markings
brown_marking -> brown_markings
grey_marking -> grey_markings
yellow_marking -> yellow_markings

Bvased an image where blue_marking was being used, suggesting the others to avoid in future.