Document uses plugins

Plugins harm SEO. Search engines can't index plugin content. Many mobile devices don't support plugins, which creates frustrating experiences for mobile users. Lighthouse flags your document when it uses plugins:

Lighthouse audit showing document uses plugins
Document uses plugins.

What causes this audit to fail

Lighthouse checks the page for tags that commonly represent plugins:

  • embed
  • object
  • applet

And then flags each tag as a plugin if its MIME type matches any of the following:

  • application/x-java-applet
  • application/x-java-bean
  • application/x-shockwave-flash
  • application/x-silverlight
  • application/x-silverlight-2

Or if the tag points to a URL with a file format that is known to represent plugin content:

  • swf
  • flv
  • class
  • xap

Learn more in Avoid making pages that rely on browser plugins.

Remove plugins

Remove the plugins from your document and convert your content to HTML. Refer to specific documentation for the plugin, for example, how to switch Flash video to HTML5 video. See also these best practices for displaying videos on the web.

More information

Each SEO audit is weighted equally in the Lighthouse SEO Score, with the exception of the manual audit, structured-data audit. Learn more in Lighthouse Scoring Guide.

Last updated: Improve article