Fix Gmail Line-Height Shifts in Apple Mail (Desktop) — React Email Guide 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 Apple Mail (Desktop) templates when using React Email.
Technical Breakdown
Apple Mail (Desktop) uses the WebKit which lacks support for standard rendering rules. This causes Gmail Line-Height Shifts elements to break or collapse when rendering templates.
React Email Behaviors
React Email relies on compiling CSS parameters dynamically. However, React Email's compiler cannot parse raw MSO conditional comments or VML structures in TSX files 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 React Email campaign manager, make sure you configure your links to run via {unsubscribeUrl}.
<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 React Email
Copy the fixed VML or table wrapper code block from the remediation box above.
Import the standard '<Html>' or '<Container>' primitives. To insert our VML or custom Outlook table markup directly, wrap the raw HTML snippet inside React's 'dangerouslySetInnerHTML' parameter on a div or span.