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Does CSS @supports Work in HTML Email?
Applies a block of CSS rules only when the browser supports a specified CSS feature.
Quick Answer
Does @supports work in HTML email?
The CSS @supports property is supported in Outlook (Mac / Web), Apple Mail, Yahoo! Mail, Samsung Email, and others. It is NOT supported in Gmail, Outlook (Windows), Thunderbird, and others. Always include a safe fallback for unsupported clients.
Which Email Clients Support CSS @supports?
CSS support for @supports across email clients
| Email Client | Desktop | Mobile / Web | Notes |
|---|---|---|---|
| Gmail | ✗ No | ✗ No | — |
| Outlook (Windows) | ✗ No | ? | — |
| Outlook (Mac / Web) | ✓ Yes | ✗ No | — |
| Apple Mail | ✓ Yes | ✓ Yes | — |
| Yahoo! Mail | ✓ Yes | ✓ Yes | — |
| Samsung Email | ? | ✓ Yes | — |
| Thunderbird | ✗ No | ? | — |
| ProtonMail | ✗ No | ✓ Yes | — |
| Fastmail | ✗ No | ? | — |
Notes
- #1 Properties not supported by the client are replaced by `_filtered_a` inside the parenthesis.
- #2 Not supported. `@supports` is transformed into `@media not all`.
Frequently Asked Questions
Related CSS Properties
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