NameIDFormat is printed but not passed to template

[FMJansen]

In the metadata template for the SP on line 18 (sp/templates/flask_saml2_sp/metadata.xml) the NameIDFormat is printed: <md:NameIDFormat>{{ nameid_format }}</md:NameIDFormat>

Another var, {{ certificate }}, is passed to the template through sp.get_metadata_context() in sp/sp.py to the Metadata class in sp/views.py. However, {{ nameid_format }} is missing there.

So I expected to see my NameIDFormat if I defined it in app.config['SAML2_SP'], but it didn’t show up.