Outlook Email Broken Layout Fix: Resolve CSS Flexbox Collapse for Editorial & Content Newsletters
Editorial newsletters rely on content layout readability and structural text spacing. If fonts default to Times New Roman or layout borders break, subscriber engagement metrics suffer. Below is the targeted integration guide to fix CSS Flexbox Collapse inside Outlook 2016 templates when using HubSpot.
Technical Breakdown
Outlook 2016 desktop uses Word's layout engine, stripping flex directions and stacking columns vertically.
HubSpot Behaviors
HubSpot's COS template manager automatically wraps content blocks in dynamic div structures to support their drag-and-drop system. These extra wrappers force styling inheritances that override inline td paddings, leading to spacing collapses in Outlook. Setting explicit table element attributes is crucial. Keep your editorial body clean. Strip redundant CSS class definitions using Vaporize to ensure the newsletter stays under Gmail's 102KB clipping ceiling.
Remediation Code Block
To resolve this, modern layouts must be compiled down to Outlook-compliant nested HTML table models. Each flex container becomes a table row, and each flex child becomes a table data cell (td) with explicit pixel or percentage widths. In your HubSpot campaign manager, make sure you configure your links to run via {{ unsubscribe_link }}.
<table role="presentation" border="0" cellpadding="0" cellspacing="0" width="100%">
<tr>
<td width="50%" valign="top">Col 1</td>
<td width="50%" valign="top">Col 2</td>
</tr>
</table>Live Code Sandbox Test
How to Deploy inside HubSpot
Copy the fixed VML or table wrapper code block from the remediation box above.
In HubSpot's Design Manager, edit the modules section. Create a 'Rich Text' or 'HTML' module block. Double-click the block, choose 'Tools' or 'Advanced', click 'Source Code', and drop the code snippet inside.