Fix Gmail Line-Height Shifts in Apple Mail (Desktop) — HubSpot Guide for eCommerce Campaigns
In eCommerce email marketing, rendering issues directly tank conversion rates and cart recoveries. Product grids, checkout CTAs, and discount banners must display flawlessly to prevent purchase drop-offs. Below is the targeted integration guide to fix Gmail Line-Height Shifts inside Apple Mail (Desktop) templates when using HubSpot.
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.
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. Double-check your dynamic product feed blocks. When injecting product loops from your catalog, ensure width sizes are explicitly handled to keep columns from overlapping.
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 HubSpot campaign manager, make sure you configure your links to run via {{ unsubscribe_link }}.
<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 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.