Browser vendors line up to remove XSLT as Chromium's November removal nears

Chrome is removing XSLT, and the rest of the browser industry followed

XSLT, or Extensible Stylesheet Language Transformations, is a web standard that lets an XML document reference a stylesheet and have the browser transform it into viewable HTML on the client. That capability is now being removed from Chrome and, with it, from most Chromium-based browsers.

According to developer David Bushell, who has been documenting the deprecation, Google initiated the removal around Halloween a year ago and other browser vendors went along rather than resisted. In his account, 17 November 2026 appears to be the date the removal takes effect, at which point pages that depend on XSLT stop rendering.

Warning banners are being injected into affected pages

Bushell reports that some Chromium-based browsers have already begun inserting a warning banner directly into pages that use XSLT. The banner, as quoted on his site, reads:

This site uses XSLT; that functionality is being removed from this browser very soon. When that happens, this page will likely no longer display correctly. You might be able to install a browser extension that allows you to continue viewing it. Otherwise, you should contact the maintainer of the site for further information.

He likens the practice to a man-in-the-middle intervention, since content the site owner never wrote is being merged into the page. He also observes that the banner appears to be implemented as an xslt-warning-banner custom element, and that it fails to render properly when it conflicts with a page's content security policy, producing, in the examples he captured, white text on a red background or plain unstyled markup. Because he tested on ungoogled-chromium, he is unsure how the banner is intended to look.

A website built to break

To make the consequences concrete, Bushell built XSLT.RIP, a site constructed with XSLT itself, meaning it will stop working once browser support ends. He also published a satirical "Intent to Deprecate and Remove Google Chrome," mirroring the format of Google's own deprecation notices. He notes that some readers initially took the site for satire, a reaction he reads as evidence of how little attention the removal has received.

The compatibility argument

Bushell's deeper complaint is about web platform governance. Backwards compatibility, the informal rule summarized as "don't break the web," was long treated as a core design principle by browser makers, he argues, and Google has now walked away from it. He also invokes the "line of death," the security boundary separating trusted browser UI from untrusted page content, and says injecting banners into pages crosses it. His sharpest criticism targets the banner's advice to contact the site maintainer: in his view, the vendor that removed the feature caused the breakage and should own it rather than redirecting users to site owners.

Why it matters

XSLT is old, but it is not unused. It dates from the era when XML was expected to be the web's universal data format, and it still sits inside publishing workflows, enterprise document pipelines and long-lived internal pages. When browser support ends, those resources will render as raw XML or nothing at all, and the remedy on offer amounts to installing an extension or asking the site owner to rebuild.

The episode also sets a precedent. If a web standard that has shipped in browsers for roughly two decades can simply be switched off, the platform's compatibility guarantees are weaker than long assumed. For maintainers, the realistic options are moving transformations server-side, since XSLT processors exist independently of browsers, or replacing XSLT pipelines entirely. Either way, with the removal apparently landing in mid-November 2026, the runway is short.