The alternate link to the page itself is missing.
A language definition is specified wrong in alternate links.
A country is specified wrong in alternate links: ar-mena
A country is specified wrong in alternate links: en-mena
A language definition is specified wrong in alternate links.
A language definition is specified wrong in alternate links.
A language definition is specified wrong in alternate links.
A country is specified wrong in alternate links: id-en
A country is specified wrong in alternate links: th-en
A language definition is specified wrong in alternate links.
A language definition is specified wrong in alternate links.
(Nice to have)