I’m interested in developing a powerup that would bridge a gap that currently exists on the web interface for Trello to enable readability for screen readers. My initial read of the docs doesn’t suggest that this kind of change is possible – could someone clarify for me? I’m thinking primarily about adding metadata in HTML, though there may be other considerations as well.
Power-Ups aren’t going to have the reach that I think you’re looking for. They can add iframe’d content to Trello, but, because they are iframes, they can’t add anything outside of their containers.
I’d guess that the best way to achieve what you’re looking for is going to be via a browser extension as those would allow you to manipulate the DOM directly.