Support CSS leading-trim
On the design side, we'd like to have more control over line spacing. Compared with other platforms, this was on the tight side in GTK 3, and has become quite compressed in GTK 4 (see libadwaita#365).
!3833 (merged) implemented support for line height but, if memory serves me correctly, that's not something we can use to resolve the line spacing issues we've seen, due to it affecting the layout around text strings. (This can be a particular issue with large single line strings, like headings.) What we need, I think, is to be able to adjust the spacing between multiple lines of text, without expanding the spacing around the text string.
There's some other relevant research and discussion in Teams/Design/os-mockups#124 .
Edited by Matthias Clasen