Send a partial update — only the codes in <code>settings[]</code> are changed, the rest are preserved.

<strong>Unsubscribe link (code 1)</strong><br/>The value must contain the <code>{{link}}</code> placeholder (the server swaps in the recipient-specific unsubscribe URL when the email is sent). A non-empty value without <code>{{link}}</code> is rejected.

<strong>Accepted preset snippets</strong> (use these verbatim, or provide any custom HTML that includes <code>{{link}}</code>):

<ol> <li><code>If you'd prefer not to receive email from me, &lt;a href="{{link}}" target="_blank"&gt;Unsubscribe here&lt;/a&gt;.</code></li> <li><code>If you don't want to receive such emails in future, &lt;a href="{{link}}" target="_blank"&gt;Unsubscribe here&lt;/a&gt;.</code></li> <li><code>Not up for all these emails? No Sweat! you can, &lt;a href="{{link}}" target="_blank"&gt;Unsubscribe here&lt;/a&gt;.</code></li> </ol>

Pass an empty string (<code>""</code>) to disable the unsubscribe link entirely.

<strong>Mutually exclusive with unsubscribe-text (code 2).</strong> Setting one to a non-empty value automatically clears the other.