Deprecations and removals in Chrome 86

Joe Medley
Joe Medley

Remove WebComponents v0

Web Components v0 was removed from desktop and Android in Chrome 80. Chromium 86 removes them from WebView. This removal includes Custom Elements v0, Shadow DOM v0, and HTML Imports.

Deprecate FTP support

Chrome is deprecating and removing support for FTP URLs. The current FTP implementation in Google Chrome has no support for encrypted connections (FTPS), nor proxies. Usage of FTP in the browser is sufficiently low that it is no longer viable to invest in improving the existing FTP client. In addition, more capable FTP clients are available on all affected platforms.

Google Chrome 72 and later removed support for fetching document subresources over FTP and rendering of top level FTP resources. Currently navigating to FTP URLs results in showing a directory listing or a download depending on the type of resource. A bug in Google Chrome 74 and later resulted in dropping support for accessing FTP URLs over HTTP proxies. Proxy support for FTP was removed entirely in Google Chrome 76.

The remaining capabilities of Google Chrome’s FTP implementation are restricted to either displaying a directory listing or downloading a resource over unencrypted connections.

Deprecation of support will follow this timeline:

Chrome 86

FTP is still enabled by default for most users, but turned off for pre-release channels (Canary and Beta) and will be experimentally turned off for one percent of stable users. In this version you can re-enable it from the command line using either the --enable-ftp command line flag or the --enable-features=FtpProtocol flag.

Chrome 87

FTP support will be disabled by default for fifty percent of users but can be enabled using the flags listed above.

Chrome 88

FTP support will be disabled.

Deprecation policy

To keep the platform healthy, we sometimes remove APIs from the Web Platform which have run their course. There can be many reasons why we would remove an API, such as:

  • They are superseded by newer APIs.
  • They are updated to reflect changes to specifications to bring alignment and consistency with other browsers.
  • They are early experiments that never came to fruition in other browsers and thus can increase the burden of support for web developers.

Some of these changes will have an effect on a very small number of sites. To mitigate issues ahead of time, we try to give developers advanced notice so they can make the required changes to keep their sites running.

Chrome currently has a process for deprecations and removals of API's, essentially:

  • Announce on the blink-dev mailing list.
  • Set warnings and give time scales in the Chrome DevTools Console when usage is detected on the page.
  • Wait, monitor, and then remove the feature as usage drops.

You can find a list of all deprecated features on chromestatus.com using the deprecated filter and removed features by applying the removed filter. We will also try to summarize some of the changes, reasoning, and migration paths in these posts.