[lucideer]

Possibly a HN formatting issue (or the commenter typed wrong first time and later edited) but the backticks weren't showing up previously.

Sorry @Traubenfuchs for the misguided explanation.

As another commenter posted, this is a template tag. Technically equivalent to doing something like styled.button('') but the template tag syntax would be used for consistency with other calls in the code (where parameterised template strings would be passed to the button/element/component method)