Almost everyone tried to go super-blonde when it was popular, with mixed results. Here's Bette Davis early in her career:
And here's Joan Crawford, looking, well...let's just say brunette suited her much better.
(screencap courtesy The Crowd Roars)
Regardless if they're in the lead or only on-screen for a moment, these "broads" with a heart of gold are just one of the things I find so irresistable about the pre-Code era.
(p.s. I know I didn't mention Joan Blondell. Shame on me! She's fantastic! Oh - and how could I forget Thelma Todd? Yikes!)