# About this case

This test case ensures that Tidy handles autonomous custom tags appropriately for HTML5 documents.

In this case, `custom-tags` is inline, and so Tidy should accept unknown tags if they look like autonomous custom elements.

This is a user-defined tag, and Tidy should provide a warning, but allow it. This is a user-defined tag, and Tidy should not provide a warning. Even though `custom-tags` is inline, this tag is configured as blocklevel in the configuration, and so will be treated as such.

This is an autonomous custom tag,, and it should show up as an inline element, as does this..