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HTML element · data last changed 10 Nov 2026

<acronym> in email clients

Works in 13 of 21. Not supported in Outlook Classic, Yahoo Mail, Yahoo Mail Android and 2 more. Untested in HEY Mail, Fastmail and Superhuman.

Your reader in Outlook Classic sees the email without <acronym>, even if it looks right where you tested it.

caniemail (MIT) via @emailens/engine 0.18.22

What to do instead in Outlook Classic

  • Buggy. title attribute is removed but keeps <acronym> tag.

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<acronym> is not among the 24 features we have screenshotted on real installs. The ones we have →

All 21 clients, problems first

ClientSupport
Outlook Classic Not supported See caveat 1
Yahoo Mail Not supported
Yahoo Mail Android Not supported
Yahoo Mail iOS Not supported
AOL Mail Not supported
HEY Mail Untested
Fastmail Untested
Superhuman Untested
Works in 13: Gmail, Gmail Android, Gmail iOS and 10 more. Show all
ClientSupport
Gmail Works
Gmail Android Works
Gmail iOS Works
Outlook 365 Works
Outlook (New) Works
Outlook iOS Works
Outlook Android Works
Outlook for Mac Works
Apple Mail Works
Apple Mail iOS Works
Samsung Mail Works
Thunderbird Works
Proton Mail Works

Caveats (1)

  1. 1. Outlook Classic: Buggy. title attribute is removed but keeps <acronym> tag.

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

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 3 Jan 2024 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping