@font-face in Thunderbird

SupportedGecko · desktop

Support Details

Always include a web-safe font stack as fallback (e.g., Arial, Helvetica, sans-serif).

Before

@font-face {
  font-family: 'CustomFont';
  src: url('custom.woff2') format('woff2');
}
h1 { font-family: 'CustomFont'; }

After

/* Keep @font-face for clients that support it */
@font-face {
  font-family: 'CustomFont';
  src: url('custom.woff2') format('woff2');
}
h1 {
  font-family: 'CustomFont', Arial, Helvetica, sans-serif;
}

Add web-safe font fallback stack

@font-face is fully supported in Thunderbird. No workarounds needed.

Other Clients

Client	Support
Gmail	Unsupported
Gmail Android	Unsupported
Gmail iOS	Unsupported
Outlook 365	Unsupported
Outlook (New)	Partial
Outlook Classic	Unsupported
Outlook iOS	Unsupported
Outlook Android	Unsupported
Apple Mail	Supported
Apple Mail iOS	Supported
Yahoo Mail	Unsupported
Samsung Mail	Supported
HEY Mail	Supported
Superhuman	Supported

Related Features

@import @keyframes @media @supports

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