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Emailens

CSS property · data last changed 10 Nov 2026

text-emphasis in email clients

Works in 9 of 21. Not supported in Gmail Android, Outlook Classic, Outlook Android and 5 more. Untested in Thunderbird, HEY Mail, Fastmail and 1 more.

Your reader in Outlook Classic sees the email without text-emphasis, even if it looks right where you tested it.

caniemail (MIT) via @emailens/engine 0.18.22

What to do instead in Outlook Classic

There is no drop-in fix for text-emphasis in Outlook Classic. Design so the email still reads without it.

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text-emphasis is not among the 24 features we have screenshotted on real installs. The ones we have →

All 21 clients, problems first

ClientSupport
Gmail Android Not supported
Outlook Classic Not supported
Outlook Android Not supported
Yahoo Mail Not supported
Yahoo Mail Android Not supported
Yahoo Mail iOS Not supported
Samsung Mail Not supported
AOL Mail Not supported
Thunderbird Untested
HEY Mail Untested
Fastmail Untested
Superhuman Untested
Works in 9: Gmail, Gmail iOS, Outlook 365 and 6 more. Show all
ClientSupport
Gmail Works
Gmail iOS Works
Outlook 365 Works
Outlook (New) Works
Outlook iOS Works
Outlook for Mac Works
Apple Mail Works
Apple Mail iOS Works
Proton Mail Works

Your next question

Every feature in Outlook Classic · All email CSS features · What real installs show

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 7 Jul 2022 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping