In M101 the DropdownWidgets are currently featuring font-weight: bold. This was established to be visually on par with buttons.
Pros for featuring bold:
- It is a similar kind of interaction widget like button, therefore should feature bold.
- It would open up a possibility of making input versus “buttonesque“ widget clearer, which opens more solutions on T147808
See OOjs UI demo HorizontalLayout section for a good comparison
- bold might be too prominent in many of the dropdown use cases and be stealing focus when not needed.