box-sizing in Yahoo Mail
caniemail.com records no behaviour caveat for box-sizing in Yahoo Mail, so the support level above is its whole answer for this pair.
Fix & Workaround
Account for padding in your width calculations (use padding on a nested element).
Before (Broken)
<div style="width: 300px; padding: 20px;
box-sizing: border-box;">
Content; total width stays 300px
</div>After (Fixed)
<div style="width: 300px;">
<div style="padding: 20px;">
Content; padding on inner element
</div>
</div>Account for padding in width manually (no box-sizing)
Other Clients
| Client | Support |
|---|---|
| Gmail | Supported |
| Gmail Android | Supported |
| Gmail iOS | Supported |
| Outlook 365 | Supported |
| Outlook (New) | Supported |
| Outlook Classic | Unsupported |
| Outlook iOS | Supported |
| Outlook Android | Supported |
| Outlook for Mac | Supported |
| Apple Mail | Supported |
| Apple Mail iOS | Supported |
| Yahoo Mail Android | Unsupported |
| Yahoo Mail iOS | Unsupported |
| Samsung Mail | Supported |
| Thunderbird | Supported |
| HEY Mail | Supported |
| Proton Mail | Supported |
| AOL Mail | Unsupported |
| Fastmail | Supported |
| Superhuman | Supported |
Related Features
See how Yahoo Mail renders box-sizing
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Last tested upstream: · Last synced by Emailens:
caniemail.com (MIT) records Feb 28, 2019 as the last time box-sizing was tested in a real client, 7 years before this sync. Syncing copies that result forward, it does not re-test it. Carried in @emailens/engine data v0.14.5.