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Does CSS max-block-size Work in HTML Email?
Sets the maximum size of an element in the block direction; equivalent to max-height in horizontal writing modes.
Quick Answer
Does max-block-size work in HTML email?
The CSS max-block-size property is supported in Outlook (Mac / Web), Apple Mail, Samsung Email, ProtonMail. It is NOT supported in Gmail, Outlook (Windows), Yahoo! Mail. Always include a safe fallback for unsupported clients.
Which Email Clients Support CSS max-block-size?
CSS support for max-block-size across email clients
| Email Client | Desktop | Mobile / Web | Notes |
|---|---|---|---|
| Gmail | ✗ No | ✗ No | — |
| Outlook (Windows) | ✗ No | ? | — |
| Outlook (Mac / Web) | ✓ Yes | ✓ Yes | — |
| Apple Mail | ✓ Yes | ✓ Yes | — |
| Yahoo! Mail | ✗ No | ✗ No | — |
| Samsung Email | ? | ✓ Yes | — |
| Thunderbird | ? | ? | — |
| ProtonMail | ✓ Yes | ✓ Yes | — |
| Fastmail | ? | ? | — |
Frequently Asked Questions
Related CSS Properties
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