Outlook Email Broken Layout Fix: Resolve Gmail Line-Height Shifts for Client Rendering Engine Anomalies
Email client rendering variations are caused by differences in parser engines. Legacy Outlook engines ignore modern block models, forcing layouts to stack vertically. Below is the targeted integration guide to fix Gmail Line-Height Shifts inside Outlook 2016 templates when using Mailchimp.
Technical Breakdown
Outlook 2016 uses the Microsoft Word (MSO) which lacks support for standard rendering rules. This causes Gmail Line-Height Shifts elements to break or collapse when rendering templates.
Mailchimp Behaviors
Mailchimp's classic template compiler injects custom inline attributes (like 'mc:edit') and automatic CSS reset sheets before delivery. If your fallback code includes head styling wrappers, Mailchimp's post-processing parser will strip media query priorities, breaking display rules in clients like iOS Mail and Gmail. The fallback table structures must have absolute styles inlined directly. Test layout code regressions side-by-side using the Campaign Diff Comparator before pushing visual style changes to your production templates.
Remediation Code Block
Define line-height as a unitless ratio (e.g. line-height: 1.4) or in explicit percentages (e.g. line-height: 140%). Avoid mixing em and px units, and apply the styles directly to the containing td or span tags containing typography. In your Mailchimp campaign manager, make sure you configure your links to run via *|UNSUB|*.
<p style="font-size: 16px; line-height: 22px; margin: 0; mso-line-height-rule: exactly;">Typography Paragraph</p>Live Code Sandbox Test
How to Deploy inside Mailchimp
Copy the fixed VML or table wrapper code block from the remediation box above.
Locate your campaign block inside Mailchimp. Drag a 'Code' block into your canvas workspace. Toggle the editor view to Source, paste the optimized code, and click Save.