Configuration

Leadlens works without configuration. Settings let you choose which files and clients to check, tune individual rules, and share those choices with a team.

Settings

Setting	Default	Description
leadlens.enable	true	Lint HTML and MJML emails.
leadlens.include	["**/*.html", "**/*.htm", "**/*.mjml"]	Glob patterns for the files to lint. Narrow this in projects that also contain HTML that isn’t email, for example ["emails/**/*.html"]. Patterns are relative to the workspace folder, as in files.exclude.
leadlens.run	"onType"	Lint as you type (onType) or only when you save (onSave).
leadlens.clients	[]	Client IDs to report on. Empty means all 21. See Previews for the IDs.
leadlens.skip	[]	Check categories to skip. See Linting for the IDs.
leadlens.rules	{}	Severity per rule: "error", "warning", "info" or "off", keyed by the rule code shown in the Problems panel.
leadlens.maxOccurrencesPerRule	20	The most underlines shown for one rule in a file.
leadlens.marketo.context	"auto"	How to interpret HTML: auto, template, email, fragment or generic. Can be set per folder. See Marketo Email Editor 2.0.
leadlens.preview.defaultClient	"gmail-web"	The client the preview opens on.
leadlens.preview.loadRemoteImages	false	Load images hosted elsewhere in the preview. Off by default because loading them can trigger tracking pixels.
leadlens.resolveStylesheetLinks	true	Analyse local linked stylesheets together with the email, and report their findings in the stylesheet.

Example

{
  "leadlens.include": ["emails/**/*.html"],
  "leadlens.clients": ["gmail-web", "outlook-windows-legacy", "apple-mail-ios"],
  "leadlens.skip": ["spam"],
  "leadlens.rules": {
    "insecure-link": "error",
    "letter-spacing": "off"
  }
}

Team configuration

Settings in VS Code belong to one person. To make the same choices for everyone working on a project, commit a .leadlensrc file to the project’s root folder:

{
  "clients": ["gmail-web", "outlook-windows-legacy", "apple-mail-ios"],
  "skip": ["spam"],
  "include": ["emails/**/*.html"],
  "rules": { "insecure-link": "error", "letter-spacing": "off" }
}

Or add the same object under a leadlens key in the project’s package.json.

The project file can set clients, skip, include and rules. For each field it sets, it overrides the editor setting; fields it leaves out are still decided by each person’s settings. rules replaces the editor’s rule map as a whole rather than merging with it, so the team’s policy is never half one source and half another.

Leadlens reloads the file when it changes. If it isn’t valid JSON, Leadlens says so in the Leadlens output channel and falls back to editor settings. An invalid severity in rules is reported the same way and ignored.

The Leadlens output channel records which fields the project file is deciding each time it’s loaded.

Moving from Emailens

Leadlens reads .emailensrc, an emailens key in package.json, explicitly set emailens.* editor settings and emailens-disable… comments, so projects set up for the Emailens extension keep working. Leadlens’s own settings and files take precedence when both are present. Disable the Emailens extension in workspaces where you use Leadlens, so files aren’t checked twice.

Workspace trust

Leadlens supports VS Code’s Restricted Mode for HTML: emails are linted and previewed in untrusted workspaces. MJML is the exception. Compiling an .mjml file runs the mjml package from the workspace, which is code from the folder you opened, so MJML files are compiled only once you trust the workspace.