Outlook Email Broken Layout Fix: Resolve Outlook Button Border Collapsing for WCAG Accessibility Violations
Accessibility failures prevent screen readers from navigating templates, isolating disabled subscribers and increasing unsubscribe rates. Below is the targeted integration guide to fix Outlook Button Border Collapsing inside Outlook Office 365 (Web) templates when using MJML Framework.
Technical Breakdown
Outlook Office 365 (Web) uses the Office Rendering Service which lacks support for standard rendering rules. This causes Outlook Button Border Collapsing elements to break or collapse when rendering templates.
MJML Framework Behaviors
The MJML transpilation compiler parses dynamic columns and wraps them in custom HTML conditional tags. If you paste direct tables or VML code blocks inside an MJML layout without proper escaping, the MJML compiler will try to clean the code, resulting in stripped Outlook namespaces and broken layouts. Inject correct table roles (role='presentation') and keep color pairings above the WCAG AA contrast threshold of 4.5:1.
Remediation Code Block
To guarantee perfectly rounded buttons inside Outlook, we must generate a hybrid VML (Vector Markup Language) roundrect structure overlaid with normal HTML tables. VML is read only by Outlook, while WebKit clients read the HTML layout. In your MJML Framework campaign manager, make sure you configure your links to run via {{unsubscribe_link}}.
<!--[if mso]>
<v:roundrect xmlns:v="urn:schemas-microsoft-com:vml" xmlns:w="urn:schemas-microsoft-com:office:word" href="{{unsubscribe_link}}" style="height:44px;v-text-anchor:middle;width:200px;" arcsize="15%" stroke="f" fillcolor="#720e9e">
<w:anchorlock/>
<center style="color:#ffffff;font-family:sans-serif;font-size:13px;font-weight:bold;">Click Here</center>
</v:roundrect>
<![endif]-->
<!--[if !mso]><!-->
<table role="presentation" border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse;">
<tr><td align="center" bgcolor="#720e9e" style="border-radius:6px;"><a href="{{unsubscribe_link}}" style="padding:12px 24px;color:#ffffff;display:inline-block;text-decoration:none;font-weight:bold;">Click Here</a></td></tr>
</table>
<!--<![endif]-->Live Code Sandbox Test
How to Deploy inside MJML Framework
Copy the fixed VML or table wrapper code block from the remediation box above.
Wrap the entire RenderOps corrected table block inside an '<mj-raw>' tag block. This tells the MJML compiler to bypass parsing on this segment, exporting the exact conditional statements into the final HTML output.