Gutenberg 24.2: React 19 by Default, Notes in the Margin and What It Means for Your Plugins

The Gutenberg plugin is where new WordPress editor features are tested before they reach core. Gutenberg 24.2, released in October 2026, is worth paying attention to for one reason above the rest: React 19 is now on by default. React is the JavaScript library the block editor is built on, and a major version change can break plugins that add custom blocks or editor panels.

It also brings visible improvements, including Notes in the margin, better Navigation block linking and much wider design controls. Here is what changed and what to do about it.

Who should care about Gutenberg 24.2

If you run a normal business site without the Gutenberg plugin installed, nothing changes for you today. These features reach you when they are merged into a WordPress core release, such as WordPress 7.2 on December 8.

You should care now if:

• You or your developer have the Gutenberg plugin installed, often to get new features early.
• You build or maintain plugins with custom blocks, sidebars or editor panels.
• You run an agency and need to know what will reach client sites in the next few months.

React 19 is on by default

Gutenberg 24.2 switches the editor to React 19 by default. If something breaks, you can turn it off under Gutenberg, Experiments while plugin authors catch up.

The WordPress core team has said a full React 19 upgrade is unlikely to land completely in WordPress 7.2, so this is the testing phase. That makes now the right time to check your plugins, before the change reaches every WordPress site.

What might break

• Custom blocks that use older React patterns, such as legacy lifecycle methods or string refs.
• Plugins that bundle their own copy of React instead of using the one WordPress provides.
• Editor sidebars and panels built with deprecated components.
• Page builder integrations that hook into the block editor.

How to test

1. Create a staging copy of your site.
2. Install Gutenberg 24.2 on staging.
3. Open posts and pages that use each of your custom blocks and plugin panels.
4. Open the browser console and look for red errors.
5. Try adding, editing, saving and previewing content.
6. If something breaks, switch React 19 off under Experiments to confirm it is the cause, then report it to the plugin author.

Notes in the margin

Notes, WordPress’s block level commenting feature, now sits on the canvas in the margin, beside the block it refers to. It can stay open alongside the block settings sidebar. This is the same change shipping in WordPress 7.2, and it makes reviewing drafts with clients or editors far smoother. We covered it in our WordPress 7.2 Beta 1 guide.

Suggestion mode, which would let reviewers propose edits to accept or reject, has been pushed to WordPress 7.3.

Navigation block link search

When adding a link in the Navigation block, you can now search across pages, posts, categories and tags in one place. It sounds small, but building menus in block themes has been one of the most common complaints from site owners moving away from classic themes. This removes a lot of friction.

Gallery sorting and duotone tinting

The Gallery block gains sorting and single colour duotone tinting, which lets you tint every image in a gallery with one brand colour for a consistent look. Combined with the responsive Gallery controls in 7.2, galleries are finally flexible enough for portfolio and product pages without a plugin.

Min width and height on 40 blocks

Around 80 design tool improvements landed in this release. The headline is that minimum width and height controls have expanded from five blocks to about 40. That makes it much easier to build consistent card layouts, hero sections and grids without custom CSS.

What is coming next: Gutenberg 24.3

Gutenberg 24.3 RC1 is already out, with rich text formatting across blocks, so formatting can be applied to a selection that spans more than one block. There is also a longer term move from @wordpress/components to a new @wordpress/ui package, which plugin developers should start planning for.

Real time collaboration is still on the way

Collaborative editing, where several people edit the same post at once, is not on the WordPress 7.2 roadmap. The team is moving to a server aware approach, and developers have been comparing sync engines such as yjs-server, DE-RTC and an intent log design. An experimental Gutenberg Sync Engines plugin exists for testing, but it is not ready for real sites.

What this means in the US, UK and Australia

The editor works the same everywhere, but timing differs. WordPress 7.2 lands on December 8, in the middle of US holiday trading, UK Christmas shopping and the run up to Australia’s Boxing Day sales. That makes October and November the right time to test React 19 compatibility, so you can update calmly in January rather than discovering broken blocks during peak season.

For agencies with clients in several countries, plan one round of plugin testing now and one after 7.2 ships. It is far cheaper than fixing broken editors one client at a time.

A checklist for plugin authors and agencies

• Test every custom block with React 19 on staging.
• Stop bundling your own React. Use the version WordPress provides.
• Replace deprecated components such as Divider, Scrollable and ZStack, which are scheduled for removal in WordPress 7.4.
• Start reading the @wordpress/ui documentation.
• Check any code that filters HTML, since wp_kses() is being rebuilt on the HTML API.

Should you use the Gutenberg plugin on a live site?

We get this question a lot. Our answer for business sites is usually no. The Gutenberg plugin updates every two weeks with experimental features, and each update can change how the editor behaves. That is great for testing and for developers, but risky for a site that earns money.

There are exceptions. If you need a specific block feature that has not reached core yet and you have someone who checks each update on staging first, it can be worth it. Otherwise, let features arrive through core releases, which are tested far more widely.

If the plugin is already installed on your live site and you are not sure why, ask whoever built the site. Removing it can change how some blocks look, so test that on staging too.

Why block themes are worth another look

A year ago, many agencies still steered clients toward page builders because block themes felt limited. Releases like 24.2 change that. With responsive controls, min width and height on 40 blocks, better navigation and form styling without CSS, block themes can now handle most small business layouts. They also tend to load faster than page builder sites, which helps Core Web Vitals and SEO. If you are planning a redesign in 2027, a block theme deserves a place on the shortlist.

Sources

• Gutenberg Times Weekend Edition 378

Need a hand with this on your own site? See our WordPress development services.

Frequently asked questions

Does Gutenberg 24.2 affect my site if I do not use the Gutenberg plugin?

Not yet. Features reach you when they are merged into a WordPress core release.

How do I turn off React 19 in Gutenberg?

Go to Gutenberg, Experiments in your dashboard and disable it.

Will React 19 be in WordPress 7.2?

A full upgrade is unlikely to land completely in 7.2, but testing now is the best way to prepare.

Can Web Brick Studio test our custom blocks?

Yes. We test custom blocks and plugins against React 19 and WordPress 7.2 on staging and fix what breaks. Contact us.