Alt text for messages

Your use case

What would you like to do?

I'd like to be able to add alt text to GIFs, images, videos and link thumbnails/previews.

Why would you like to do it?

I am in a chat group on WhatsApp currently and there is a person who is visually impaired. Sometimes a joke gets made using a GIF, and it would be nice to add the alt text in a way that that user can access it but it doesn't have to be implemented via some work around such as a caption or another message, such that if a person forgets to add an alt text they can go back to the message and add it later.

How would you like to achieve it?

Being able to add the alt text during upload and also being able to modify a message if it was forgotten, because accessibility is a thing people are likely to forget, so it should be amendable.

Have you considered any alternatives?

I saw #378, but as I said I don't want to use a workaround. Native support would be ideal.

Additional context

No response

No files, tests, or entry points are named. Start by reviewing the linked alternative issue #378 and the relevant Element client scope, then define how alt text is added during upload and edited later for GIFs, images, videos, and link previews. Done means native accessible text is available without a caption or separate message.