On November 17, 2026, Chrome 158 stops running XSLT, the old technology that turns an XML file into a styled web page. Every WordPress XML sitemap uses it. WordPress core’s wp-sitemap.xml does, and so do the sitemaps from Yoast SEO, Rank Math and All in One SEO. Some Chrome users already see a banner on their sitemap that says “This site uses XSLT; that functionality is being removed from this browser very soon.”
Your rankings are not at risk. What breaks is the friendly table people see when they open a sitemap in Chrome. Here is what changes, what WordPress and the SEO plugins are doing about it, and what I’d do on a WordPress site this week.
Key takeaways
- Chrome 158 stops running XSLT on November 17, 2026, so styled XML sitemaps lose their formatting. Every WordPress sitemap uses XSLT, including core’s wp-sitemap.xml and the sitemaps from Yoast SEO, Rank Math and All in One SEO. arvindkumar.ca
- Your rankings are not at risk. Search engines read the XML and never run the stylesheet, so the URLs, dates and structure they rely on stay the same. arvindkumar.ca
- People who open a sitemap in Chrome will see a notice and the raw XML tree. Every URL and date is still there, but the table, column headings and clickable links are gone. arvindkumar.ca
- None of WordPress core, Yoast SEO, Rank Math or All in One SEO has shipped a fix yet. Core and Yoast have open proposals, and Core’s stylesheet filter can only remove the stylesheet line, not point it at a CSS file. arvindkumar.ca
- For most sites, check Search Console and keep your SEO plugin updated. If people use your sitemap as a list of pages, give them a real Sitemap page built with the Page List and Archives blocks. arvindkumar.ca
- On core’s sitemap, you can remove the stylesheet line early with two filters in an mu-plugin. Only do it if the banner is confusing people now, because Firefox and Safari still run XSLT today. arvindkumar.ca
- Skip the origin trial and the XSLT polyfill for a sitemap. The trial only delays the change until August 17, 2027, and the polyfill means changing how your SEO plugin writes the sitemap, which is more work than the page is worth. arvindkumar.ca
Summarised from this post, formatted for answer engines.
What is changing in Chrome on November 17?
Chrome is removing XSLT, so a sitemap that asks for an XSL stylesheet will no longer be styled. Chrome’s deprecation page sets out the dates:
- Chrome 158, November 17, 2026: XSLT stops working on the stable release for everyone except sites in Chrome’s origin trial and browsers under an enterprise policy.
- Chrome 176, August 17, 2027: the origin trial and the enterprise policy end, and XSLT is off for everyone.
- Still supported: an
xml-stylesheetline that points to a CSS file instead of an XSL file.
A WordPress sitemap starts with a line like this, and it is that line that stops working:
<?xml-stylesheet type="text/xsl" href="https://example.com/wp-sitemap.xsl" ?>Does Chrome dropping XSLT hurt my SEO?
No. Search engines read the XML in your sitemap and never run the stylesheet, so the URLs, dates and structure they rely on are exactly the same after November 17. The stylesheet only exists to make the file readable for a person. Yoast’s issue on the change says the same about its own sitemaps: the XML body stays as it is.
Who notices, then? People who open the sitemap in a browser: you, your editors, a client checking that a page is listed, an agency doing an audit. That is worth handling, but it is not an emergency.
What will people see when they open my sitemap in Chrome?
A notice and the raw XML, not a blank page. Tested with WordPress 7.1.3’s core sitemap in Chromium with XSLT switched off, the styled table was replaced by this line, with the XML tree underneath:
This document cannot be formatted as intended. It uses XSLT, which the browser does not support. You might be able to install a browser extension that allows you to view it.Every URL and date is still there, just without the table, the column headings or clickable links. With the stylesheet line removed, the same browser shows Chrome’s usual “This XML file does not appear to have any style information associated with it” note and the same tree.
What are WordPress and the SEO plugins doing about it?
They are still working on it, and none has shipped a fix yet:
- WordPress core (wp-sitemap.xml): Trac ticket #65593 proposes removing core’s XSL stylesheet. It is awaiting review, with no release assigned. A linked pull request would remove the stylesheet line and let you add .html to a sitemap URL to get a page rendered on the server instead.
- Yoast SEO: an open issue and pull request swap its XSL stylesheet for a CSS one, which Chrome keeps supporting. In the browser view, links stop being clickable, last-modified dates show as raw timestamps and the URL count disappears. No release is named yet.
- Rank Math: the sitemap code in version 1.0.280 still prints an XSL stylesheet line, and a support thread about the Chrome banner, opened October 22, had no reply as of October 23.
- All in One SEO: the code in its public repository, version 5.0.4, still prints an XSL stylesheet line too.
One thing to know before you look for a filter: WordPress core writes type="text/xsl" into the stylesheet line itself, so pointing core’s stylesheet filter at a CSS file won’t work. The filter can only remove the line.
What should I do about my WordPress sitemap now?
Confirm search engines are fine, decide whether people need a readable sitemap, then pick the lightest option that covers them.
- Find out which sitemap your site serves. Open /wp-sitemap.xml for core, or /sitemap_index.xml for Yoast and Rank Math, and look for the
xml-stylesheetline in the page source. It worked if you know which plugin’s update to watch for. - Check the sitemap in Google Search Console, under Indexing, Sitemaps. It worked if the status says Success and the discovered URL count looks right. Nothing about that changes on November 17.
- Keep your SEO plugin updated, and check the sitemap in Chrome after each release until the banner is gone. That is the whole job for most sites.
- If people use your sitemap as a list of pages, give them a real page. Create a Sitemap page and add the Page List block for your pages and the Archives block for your posts. It worked if the page lists everything with working links, in any browser.
If you are on core’s sitemap and the banner itself is the problem, you can remove the stylesheet line now. Tested on WordPress 7.1.3, these two filters remove the line from the index and from every sitemap, and leave the XML otherwise unchanged. Save it as a file in wp-content/mu-plugins/:
<?php
/**
* Plugin Name: Remove the XSL stylesheet from core sitemaps
*/
add_filter( 'wp_sitemaps_stylesheet_url', '__return_false' );
add_filter( 'wp_sitemaps_stylesheet_index_url', '__return_false' );Think before you add it. Firefox and Safari still run XSLT today, so this takes the styled view away from their users weeks before they would lose it. I’d only do it if the banner is confusing people now.
Should I use Chrome’s origin trial or the XSLT polyfill?
Not for a sitemap. The origin trial only keeps XSLT working until August 17, 2027, and you would be signing up and managing a token to postpone a cosmetic problem. I walked through how origin trial tokens work on WordPress in How to add the WebMCP origin trial token to WordPress, and the effort makes sense there because the feature is new, not on its way out.
Chrome also offers a polyfill, a script that runs the XSLT itself. For an XML page, Chrome’s instructions put a script line inside the document’s root element, which means changing how your SEO plugin writes the sitemap. That is more work than the page is worth when an HTML sitemap page does the same job in every browser.
So the short version: your sitemap keeps working for Google and Bing, Chrome users see plain XML after November 17, and the fix that lasts is a sitemap page written for people. Check Search Console, update your SEO plugin when its CSS stylesheet arrives, and only remove the stylesheet line early if the banner is causing confusion.