mandatory fields not recognizable by people with color vision deficiency

[mkc-ka]

Is this a bug or feature request?

feature request

What is the current behavior?

the mandatory fields are currently marked by a 2px blue border. People with color vision deficiency (blue or green) have a hard time recognizing these fields.
example:

especially when zoomed out (on my PC chrome with 90% zoom) the border switches to 1px width.

Which are the steps to reproduce?

What is the expected or desired behavior?

Either a simple tweak to the frontend like thicker border or an icon / exclamation mark next to the mandatory fields, or a bigger project like color themes / accent colors selectable by the user.