Zoom-ratio-default doesn't trigger automatically..?

Not sure what I’m doing wrong here. I’ve set zoom-ratio-default for document-buffer, but the zoom ratio is more often than not set as 1.0 when entering a site.
I have to call reset-page-zoom for the zoom to be set to zoom-ratio-default

(define-configuration document-buffer
  ((zoom-ratio-default 1.2)))

@simendsjo I can reproduce this bug. Could you open an issue on GH? Thanks!