The title of a dialog modal is getting truncated

Problem/Motivation

During the review of ✨ Open the "discard changes" dialog in the off-canvas tray Active (in #40 ✨ Open the "discard changes" dialog in the off-canvas tray Active ) we've noticed that the title of dialog modals in Olivero are getting truncated due to the styling:

If you replace the h1 wrapping the title of the dialog modal with a span with devtools, the title becomes fully legible:

Some context, until a few weeks ago, a span element was used for wrapping the title of dialog (modals) in jQuery UI in Drupal, which was semantically wrong and a problem for screenreader users. 📌 Update to jQuery 1.14.1 and use the newly added option for dialog modal headings Active solved that problem, for dialogs the span got replaced by h2s, and for dialog modals by h1s. In Claro that change caused no visual changes, but I was unaware that dialogs and dialog modals would be available for frontend themes like olivero and umami as well, and therefore have not tested for that detail, which lead to results seen in the screenshots. :/

Steps to reproduce

- apply MR11723 ( ✨ Open the "discard changes" dialog in the off-canvas tray Active )
- create a layout in layout builder that is using olivero click the discard.

Proposed resolution

Adjust the styling for h1 and h2 in dialog titles so that the titles are don't get truncated.

Remaining tasks

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet