HTML documents should have a valid IETF's BCP 47 `lang` attribute.
== Why is this an issue?
Screen readers require a specified language to function correctly. Without it, they default to the user's set language, causing issues for multilingual users. Specifying a valid language ensures correct pronunciation and a less confusing experience.
== How to fix it
Add a `lang` attribute with a valid IETF BCP 47 value.
=== Code examples
==== Noncompliant code example
[source,html,diff-id=1,diff-type=noncompliant]
----
----
==== Compliant solution
[source,html,diff-id=1,diff-type=compliant]
----
----
== Resources
=== Documentation
* W3C, https://www.w3.org/International/articles/language-tags/[Language tags in HTML and XML]