Add relative units for font size option

[iamtakashi]

The custom font size option is really useful, but the lack of relative units has been a problem to make patterns work well in both large and small screens.

It'd be great if we could have some the relative units, just like the cover block height control.

With the vw unit, this sort of type treatment would be possible, I think.

I've seen this topic has come up before, and I'll apologise if there is a better thread to discuss this. If there is please point me at there.

[carolinan]

Related:
https://make.wordpress.org/themes/2020/05/20/block-based-theme-meeting-notes-20-may-2020/

#22505

[aristath]

Expanding on this one, it would be useful to just have a freeform option.
Values don't necessarily need to be 10px, 2em, 3vw etc... Some cases require more elaborate values.
Maybe I want to use calc(14px + 0.5vw) and have responsive typography. Or maybe I just want to use clamp(). Or even just use a css-variable and type var(--base-font-size).

Forcing users to pick a numeric value and a unit will cover a lot of cases, but not all. It will still limit things and prevent valid use-cases that make sense.

[jorgefilipecosta]

I agree with what is being said here. Ideally, the font size picker component would be expanded to support string values.
When it can parse things like "1em" it would render relevant pickers with the correct units. If it can not parse because it is a complex value like calc(14px + 0.5vw) it would show a simple input field with the string.

The same would happen for all controls where we accept value/units or more complex CSS.