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CSS property · data last changed 10 Nov 2026

[aria-labelledby] in email clients

Works in 7 of 21. Not supported in Gmail, Gmail Android, Gmail iOS and 10 more. Untested in Superhuman.

Safe to leave in: where it is not supported, the email renders the same.

caniemail (MIT) via @emailens/engine 0.18.22

What to do instead in Outlook Classic

  • Buggy. id is removed.

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[aria-labelledby] is not among the 24 features we have screenshotted on real installs. The ones we have →

All 21 clients, problems first

ClientSupport
Gmail Not supported See caveat 1
Gmail Android Not supported See caveat 1
Gmail iOS Not supported See caveat 1
Outlook 365 Not supported See caveat 1
Outlook (New) Not supported See caveat 1
Outlook Classic Not supported See caveat 2
Yahoo Mail Not supported
Yahoo Mail Android Not supported
Yahoo Mail iOS Not supported
Thunderbird Not supported
HEY Mail Not supported
AOL Mail Not supported
Fastmail Not supported See caveat 1
Superhuman Untested
Works in 7: Outlook iOS, Outlook Android, Outlook for Mac and 4 more. Show all
ClientSupport
Outlook iOS Works
Outlook Android Works
Outlook for Mac Works
Apple Mail Works
Apple Mail iOS Works
Samsung Mail Works
Proton Mail Works

Caveats (2)

  1. 1. Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Fastmail: Buggy. id prefix mismatched. The id value is prefixed but not the aria-labelledby value.
  2. 2. Outlook Classic: Buggy. id is removed.

Caveats as recorded by caniemail (MIT), one entry per wording.

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 8 Apr 2022 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping