CSS property · data last changed 10 Nov 2026
unit-vh in email clients
Works in 17 of 21. Not supported in Outlook Classic and Fastmail. Partial in Apple Mail iOS. Untested in Superhuman.
Your reader in Outlook Classic sees the email without unit-vh, 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 unit-vh in Outlook Classic. Design so the email still reads without it.
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unit-vh is not among the 24 features we have screenshotted on real installs. The ones we have →
All 21 clients, problems first
| Client | Support |
|---|---|
| Outlook Classic | Not supported |
| Fastmail | Not supported |
| Apple Mail iOS | Partial See caveat 1 |
| Superhuman | Untested |
Works in 17: Gmail, Gmail Android, Gmail iOS and 14 more. Show all
| Client | Support |
|---|---|
| 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 |
| Yahoo Mail | Works |
| Yahoo Mail Android | Works |
| Yahoo Mail iOS | Works |
| Samsung Mail | Works |
| Thunderbird | Works |
| HEY Mail | Works |
| Proton Mail | Works |
| AOL Mail | Works |
Caveats (1)
- 1. Apple Mail iOS: Buggy. Value resolves to zero
Caveats as recorded by caniemail (MIT), one entry per wording.
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