Support browser font size settings

[kerryarchibald]

Your use case

What would you like to do?

Set HTML base font size to 100% instead of 16px

Why would you like to do it?

How would you like to achieve it?

Note: Once we set the html element font size to 100%, we'll still need to make sure the text scales when using the slider in Settings > Appearance > Font size. We should honor both the browser font size plus the font size slider setting. For example, by setting html font size to something like calc(100% + 1px), calc(100% + 2px) and so on. We'd also need to change the values displayed in the slider to something relative, default instead of 16, large or +1 instead of 17, and so on.

Have you considered any alternatives?

No response

Additional context

https://github.com/vector-im/customer-retainer/issues/47

[robintown]

Fixed by matrix-org/matrix-react-sdk#12246