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Does CSS inset Work in HTML Email?
Shorthand that corresponds to the `top`, `right`, `bottom`, and/or `left` properties
Quick Answer
Does inset work in HTML email?
The CSS inset property is supported in Apple Mail, Thunderbird. It is NOT supported in Gmail, Outlook (Windows), Outlook (Mac / Web), and others. Always include a safe fallback for unsupported clients.
Which Email Clients Support CSS inset?
CSS support for inset across email clients
| Email Client | Desktop | Mobile / Web | Notes |
|---|---|---|---|
| Gmail | ✗ No | ✗ No | — |
| Outlook (Windows) | ✗ No | ? | — |
| Outlook (Mac / Web) | ✗ No | ✗ No | — |
| Apple Mail | ✓ Yes | ✓ Yes | — |
| Yahoo! Mail | ✗ No | ✗ No | — |
| Samsung Email | ? | ✗ No | — |
| Thunderbird | ✓ Yes | ? | — |
| ProtonMail | ? | ? | — |
| Fastmail | ? | ? | — |
Frequently Asked Questions
Related CSS Properties
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