Platform: Website
Browser, if a website issue: Firefox
URLs (aka web addresses) of any relevant observations or pages: https://www.inaturalist.org/projects/(any traditional project)
Screenshots of what you are seeing:
Under the most observed species column on traditional projects homepage, species are displayed by common name, and scientific if there is no common name despite my display setting for Common / Scientific Name Display Order under my profile being set to Scientific name (Common name).
