WordPress 7.1, named "Mary Lou" after the jazz pianist and composer Mary Lou Williams, launched at WordCamp US on 19 August 2026. It is the second major release of the year, three months after 7.0 "Armstrong" in May. Most of what changed matters more to people who edit sites every day than to anyone reading the changelog once. Here are the parts that touch a running site.
Responsive block styles without custom CSS
The Site Editor now styles blocks per breakpoint. Until now, making a block look different on a phone meant custom CSS or a plugin. In 7.1 it is in the same style controls as everything else. Expect fewer "the site looks wrong on my phone" tickets, and check any custom CSS that was written to fix exactly that, because it now stacks with the native option.
Media: compression at upload, new formats
Images are compressed and resized in the browser at upload time, and AVIF, HEIC and HDR gain-map formats are supported natively. For clients uploading photos straight from a phone this removes a step. Test it against your own media library: a theme or plugin that assumes JPEG and PNG may display existing media differently.
New blocks, better Notes, a persistent admin bar
Two new blocks ship: Playlist and Tabs. Notes, the block-level comments introduced in 6.9 "Gene" in December 2025, gain rich text, @mentions and inline annotations. The admin bar now stays visible across editors instead of disappearing depending on the screen.
For developers: SVG icon API, Abilities API, admin design system
7.1 adds a public SVG Icon API, expands the Abilities API and introduces a design system for admin theming. The release also carried unusual scale: over 800 contributors, more than 170 of them for the first time, 1,500 or more enhancements and fixes, and full translations in 20 or more locales at launch.
The order in which to update a fleet
| Step | Why |
|---|---|
| 1. Read your theme's and page builder's 7.1 notes | Responsive block styles and the new media pipeline are the two areas most likely to touch existing customisations. |
| 2. Update one low-risk site first | A brochure site with the same theme as the shops. Read it on a phone afterwards. |
| 3. Then the sites with custom mobile CSS | Check that the old fixes do not now double up with native responsive styling. |
| 4. Shops last, with a restore point | WooCommerce sites carry the most plugins and the most revenue per hour of downtime. |
| 5. Keep the difference | Whatever tool you use, keep a record of what the update changed per site. Two weeks later that record is how you find a cause. |
7.1's release candidate also absorbed the fix from the 7.0.4 security release published a week earlier, so sites that update straight to 7.1 get that patch as part of the same update.
What your clients will notice, and what to tell them
Most of 7.1 is invisible to a visitor. Three things are not. The editor looks slightly different, with the admin bar now staying put. Photos uploaded from a phone are compressed on upload, so a client who used to be told "the image is too large" will not be. And the responsive style controls mean a client with editor access can now change how a block looks on mobile, which is a feature and also something to mention before they discover it on the live site. A two-line note to editors before the update saves the "did you change something?" e-mail afterwards.
A test plan you can run in fifteen minutes per site
- Home page, one product or service page, the contact page and one blog post, on a desktop and on a phone. Look at spacing and images, the two areas the release touches.
- Submit the contact form once and check the e-mail arrives.
- Open the editor on one existing page and one new page. Save without changing anything and check nothing moved.
- Upload one photo from a phone and check how it looks in the media library and on a page.
- On a shop: add a product to the cart and reach the payment step. Do not pay; the test is whether the page renders and the totals are right.
If all five pass, the site is fine for the vast majority of what changed. If one fails, the restore point you took before the update is the way back while you read the theme's release notes.
Sources
- WordPress.org, "WordPress 7.1 'Mary Lou'"wordpress.org/news, published 19 August 2026
- WordPress.org release index, version numbers and dates for 7.0 "Armstrong", 6.9 "Gene" and 6.8 "Cecil"wordpress.org/news/category/releases
Justin van Dongen