overflow in Fastmail
Works overflow works in Fastmail.
Works in 4 of 21 · partial in 16 · not supported in 1
Which clients
- Works
- Thunderbird, HEY Mail, Fastmail, Superhuman
- Partial
- Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook iOS, Outlook Android, Outlook for Mac, Apple Mail, Apple Mail iOS, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Proton Mail, AOL Mail
- Not supported
- Outlook Classic
The fix for the clients that need it
Needed in 17 of 21: Outlook Classic, Gmail, Gmail Android and 14 more.
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Your next question
- Does unit-vw work in Fastmail?
Works in 18 of 21 · not supported in 2 · 1 untested
- Does unit-vh work in Fastmail?
Works in 17 of 21 · partial in 1 · not supported in 2 · 1 untested
- Does mix-blend-mode work in Fastmail?
Works in 13 of 21 · partial in 2 · not supported in 6
- Does writing-mode work in Fastmail?
Works in 13 of 21 · partial in 2 · not supported in 6
- Does filter work in Fastmail?
Works in 7 of 21 · not supported in 14
- Does grid-template-columns work in Fastmail?
Works in 7 of 21 · partial in 1 · not supported in 13
Questions
- How many email clients support overflow?
- It works in 4 of 21, partial in 16, not supported in Outlook Classic.
- Does overflow work in Apple Mail?
- overflow is partly supported in Apple Mail. Closest to Fastmail: Apple Mail, which agrees on 192 of the 235 features both are tested on.
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Real captures 14 Oct 2026 on 10 installs · caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 27 May 2025 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping