border-inline
CSS property · 2 supported, 0 partial, 10 unsupported across 15 clients
Client Support
| Client | Category | Engine | Support |
|---|---|---|---|
| Gmail | webmail | Gmail Web | Unsupported |
| Gmail Android | mobile | Gmail Mobile | Unsupported |
| Gmail iOS | mobile | Gmail Mobile | Unsupported |
| Outlook 365 | webmail | Outlook Web | Unsupported |
| Outlook (New) | desktop | Outlook Web | Unsupported |
| Outlook Classic | desktop | Microsoft Word | Unsupported |
| Outlook iOS | mobile | Outlook Mobile | Unsupported |
| Outlook Android | mobile | Outlook Mobile | Unsupported |
| Apple Mail | desktop | WebKit | Supported |
| Apple Mail iOS | mobile | WebKit | Supported |
| Yahoo Mail | webmail | Yahoo | Unsupported |
| Samsung Mail | mobile | Samsung | Unsupported |
| Thunderbird | desktop | Gecko | Unknown |
| HEY Mail | webmail | WebKit | Unknown |
| Superhuman | desktop | Blink | Unknown |
Client-by-client behaviour for border-inline
Fully supports border-inline (2): Apple Mail, Apple Mail iOS.
No support (10): Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook Classic, Outlook iOS, Outlook Android, Yahoo Mail, Samsung Mail. Plan fallbacks for these clients before relying on border-inline in production sends.
Behaviour unverified in: Thunderbird, HEY Mail, Superhuman.
Fixes & Workarounds
Gmail
Unsupported"border-inline" is not supported in this email client.
Gmail Android
Unsupported"border-inline" is not supported in this email client.
Gmail iOS
Unsupported"border-inline" is not supported in this email client.
Outlook 365
Unsupported"border-inline" is not supported in this email client.
Outlook (New)
Unsupported"border-inline" is not supported in this email client.
Outlook Classic
Unsupported"border-inline" is not supported in this email client.
Outlook iOS
Unsupported"border-inline" is not supported in this email client.
Outlook Android
Unsupported"border-inline" is not supported in this email client.
Yahoo Mail
Unsupported"border-inline" is not supported in this email client.
Samsung Mail
Unsupported"border-inline" is not supported in this email client.
Related Features
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Try Emailens FreeSupport data last updated Apr 27, 2026 · synced from caniemail.com via @emailens/engine.