Changelog · Leadlens

1.0 — October 2026

The first release of Leadlens: email preview and linting for Adobe Marketo Engage.

Live previews across 21 email clients, including Gmail, Outlook, Apple Mail, Yahoo Mail and Samsung Mail, in light and dark mode.
Side-by-side comparison of up to four clients, and paired light and dark views of a single client.
Viewport presets from 320 to 768 px, custom widths from 240 to 1,600 px, and 50–150% zoom, each independent of the others.
Saved client sets for the combinations you check most often.
Local images referenced by relative paths, including CSS backgrounds, responsive srcset images and Outlook VML fills. Only files inside your workspace are shown.
Remote images are blocked by default, so previews never trigger tracking pixels.
The preview tab shows the Leadlens icon, in versions for light and dark themes.

Automatic detection of Email Editor 2.0 templates, complete Marketo emails and standalone components, with a setting to choose explicitly for inherited HTML.
String, List, Number, Color, Boolean, HTML and Image variables, with global and module-scoped local preview values.
Token fallbacks, with runtime-only tokens clearly marked as unresolved.
Validation of declarations, variable references, tokens, containers, modules and editable regions, including legacy mktEditable content.
Component-in-template previews for custom HTML placed inside an editable region.
A read-only view of the prepared HTML that each preview renders.
Outline and breadcrumb navigation, hovers, Go to Definition for variables, variable completions and declaration snippets.
Marketo-safe quick fixes, such as correcting single-braced tokens and adding a missing mktoName. Fixes never rewrite dynamic tokens, Outlook conditional comments or VML.

Diagnostics for client support, Outlook VML, stripped styles, accessibility, links, images, spam signals, size and Gmail clipping, overflow, dark- and mobile-mode contrast, and template variables.
Findings mapped back to the exact source line, through Marketo substitutions, composed components and linked stylesheets.
Compatibility hovers, per-client scores, a full report, and quick fixes including Fix All on save.
Per-rule severities, skippable check categories, team configuration in .leadlensrc, and comments to silence individual findings.
MJML support using the workspace’s own compiler, in trusted workspaces.

Licence notices for every bundled open-source component, and for the caniemail compatibility data, are installed with the extension in THIRD_PARTY_NOTICES.md.

include patterns that name a folder, such as emails/**/*.html, now match files in that folder. They are relative to the workspace folder; previously such a pattern matched nothing, so Leadlens ignored every file.
Local images now appear in the preview. They were found but failed to load, because the preview’s sandboxed email frame can’t fetch files from VS Code; Leadlens now embeds them directly.

Previews simulate each client’s documented behaviour; they are not screenshots from the real applications.
Email Script (Velocity) tokens are not executed. Runtime Marketo output is shown only when a local value or fallback is available.
Email Designer output is supported as ordinary HTML.