[Progress] Variants do not communicate role or state

[brucelawson]

Duplicates

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Latest version

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Current behavior 😯

The components seldom communicate role or state to assistive technology. See video

https://user-images.githubusercontent.com/378048/157297201-9d86626d-0bb3-465e-aba4-1a39dbded27c.mp4

This is a level A failure of WCAG.

Expected behavior 🤔

Assistive technology should be told that the tab is busy, and when it ceases to be busy. and, if there is a numeric %age completed shown, this should periodically be communicated to the assistive technology (perhaps using an aria live region). E.g. https://dequeuniversity.com/library/aria/progress-bar-bounded

Consider not showing movement longer than 5 seconds to people who prefer reduced motion.

Steps to reproduce 🕹

Steps:

Context 🔦

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Your environment 🌎

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