1779302 - Update h1 titles on about pages

Status: NEW

(Firefox :: Theme, enhancement)

Description

[James Teow [:jteow]]

While working on bug 1737043, I received a request to change the style of the title to be updated based on a Figma file. The title has a smaller font-size and a thicker font-weight.

Initially, I attempted to make the change have a wider reach than just the aboutNetError page in order to be more consistent, but upon looking at a couple other about pages, I realized some pages didn't look as good with the smaller text as the text width of the title helped make the content area larger. Without it, the content area became squarish, so the minimum width of the content might need to be adjusted.

Additionally, the visual hierarchy of some pages don't look as good with the smaller text, such as about:tabcrashed

Lastly, quite a number of about pages don't use the title-text class and instead inherit their styling from html|h1 in common-shared.css. One such example of this is about:profiles.