Qt lacks an accessible role for block quotes

ARIA other accessibility APIs define an accessible role to indicate that content is a block quote, see: https://w3c.github.io/aria/#blockquote:
"A section of content that is quoted from another source."

The W3C Core Accessibility mappings spec describes how to map the role to platform APIs:

https://www.w3.org/TR/core-aam-1.2/#role-map-blockquote

However, Qt currently lacks an equivalent for that role, making it impossible for e.g. browsers or text editors like LibreOffice to properly expose such content to Assistive Technologies.