fix: navigation_title not mandatory

[nsd0sneumann]

No description provided.

[mike4git]

Of course you can merge this but it's only the beginning of a long list of requirements to mandatory or non-mandatory fields which should be exported or not.

[nsd0sneumann]

Of course you can merge this but it's only the beginning of a long list of requirements to mandatory or non-mandatory fields which should be exported or not.

maybe. But at the moment I don't know them yet ;)