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CSS property · data last changed 10 Nov 2026

modern-color in email clients

Works in 4 of 21. Not supported in Gmail, Gmail Android, Gmail iOS and 13 more. Untested in Superhuman.

Your reader in Outlook Classic sees the email without modern-color, 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 modern-color in Outlook Classic. Design so the email still reads without it.

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

Caveats (2)

  1. 1. Gmail, Gmail Android, Gmail iOS: Using this syntax for an inline style will remove all inline styles applied to that element.
  2. 2. HEY Mail, Fastmail: Depends on browser support.

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

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 18 Jan 2023 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping