Use of Unicode braille in aria-braillelabel vs (draft) ARIA 1.3 guidance

Summary

MathJax 4.1.1 appears to populate aria-braillelabel with Unicode braille pattern characters. The ARIA 1.3 draft currently advises authors not to use Unicode braille characters for this attribute. I’m trying to understand whether MathJax’s approach is based on tested AT behavior and whether this represents a deliberate divergence from the spec guidance.

Source of Public Working Draft:
https://www.w3.org/TR/wai-aria-1.3/#aria-braillelabel

Observations

The ARIA model for aria-braillelabel assumes that assistive technologies will translate text into braille according to user preferences (e.g., Nemeth, UEB, contraction level). Supplying Unicode braille patterns effectively bypasses that translation step.

However, MathJax appears to generate pre-translated braille and expose it directly via aria-braillelabel.

This raises a few interoperability questions:

• Do major screen readers (e.g., NVDA, JAWS, VoiceOver) and/or refreshable braille displays reliably present Unicode braille patterns from aria-braillelabel as intended?
• Is the behavior consistent across different braille displays and translation settings?
• Are these characters passed through literally, or are they subject to re-translation or filtering?

Questions for the MathJax community:

• Is the use of Unicode braille in aria-braillelabel intentional?
• What AT + braille display combinations have been tested with this approach?
• What behavior was observed (e.g., passthrough vs translation)?
• Was using plain text (to allow AT-driven translation) considered, and if so, why was it rejected?
• Are there known cases where this approach fails or produces inconsistent output?

Thanks in advance for any insights and functional performance results.

No MathJax file, test, or entry point is identified. Start by reviewing the linked ARIA 1.3 guidance and testing aria-braillelabel with the named screen readers and braille displays; done means documenting whether Unicode braille is intentional, interoperable, and consistent with the guidance.