Mercury Editor 3 Reaches Stable Release With Autosave, Undo and Component Navigation

Mercury Editor reached its first stable 3.x release on 14 October 2026, followed by a compatibility update on 15 October. The Drupal visual page builder's 3.x development cycle brought autosaving, undo and redo controls, and a component outline for navigating page layouts. The 3.0.0 release marks these capabilities as part of a stable branch, rather than introducing them all for the first time.

Built around Drupal's Paragraphs system, Mercury Editor lets authors work with a visual page preview and editing controls in a resizable tray. Sites configured with Layout Paragraphs can arrange components and nested layouts while previewing changes. The new component outline helps editors navigate those layouts, while autosave and undo/redo support everyday editing tasks.

The principal authoring improvements were already identified in the first 3.x alpha release in July 2025. Later prereleases refined undo/redo state management, preview rendering and interface behaviour. These changes accumulated during development; the 14 October stable release is the milestone that makes the 3.x branch a stable upgrade option.

The upgrade also involves Layout Paragraphs 3, which reached its own stable release on 9 October 2026. Its 3.x changes include click-based rather than hover-based component selection, SortableJS in place of Dragula for drag-and-drop operations, and revised JavaScript events. Drupal teams with customised page-building interactions should assess those changes separately from Mercury Editor's own features.

A day after the stable milestone, Mercury Editor 3.0.1 fixed a compatibility issue between its Mercury Editor Templates submodule and the latest Layout Paragraphs version. The release notes describe this specific integration fix, not a general failure across all Mercury Editor installations.

Mercury Editor 3.x supports Drupal 10.3 and compatible Drupal 11 versions; Drupal 12 support is not listed in the stable release information. Before upgrading, maintainers should check the installed release's dependency constraints, particularly Layout Paragraphs and other supporting modules, along with any custom integrations or JavaScript behaviour.

For teams already using Paragraphs-based visual editing, Mercury Editor 3 provides a stable route to the revised authoring controls without requiring a move to a different content model. The main decision is whether the site's existing Layout Paragraphs configuration and customisations are ready for the 3.x upgrade.