Appearance

Lettr — the email API from the team behind Topol EditorThe email API that ships in an afternoonFrom the team behind Topol Editor

Merge tag previews ​

Merge Tag Previews replace merge tags with test values inside Preview mode, so a template can be checked with realistic content before it is sent.

To use this feature, enable it in the TOPOL_OPTIONS configuration:

ts
enableMergeTagPreview: true,

INFO

This works independently of Smart Merge Tags. Only enableMergeTagPreview is required.

Once enabled:

  1. Navigate to Preview mode inside the editor.
Merge Tag Preview Button
  1. Click the Merge Tags - Preview button to toggle the Merge Tag Preview panel.
Merge Tag Preview Panel
  1. Click it to view mock values for all Merge Tags present in your email.
Merge Tag Preview Panel

The panel lists the tags used in the current template, along with any tag referenced by a Conditional Content variant condition. A Show unused toggle extends the list to every defined merge tag.

To pre-fill these test values, add the defaultValue property to a Merge Tag's configuration and the Preview populates the input automatically. For details and an example, see Default Merge Tag Values.