Map Converter cannot resolve complex ENV var

[svenhaag]

I tried to set env var as follows: TEST_LANGUAGE_DE-ETR=Einfache Sprache and got the following error: java.util.NoSuchElementException: SRCFG00014: The config property test.language.de-etr#value is required but it could not be found in any config source at injection point:

@Inject
@ConfigProperty(name = "test.language")
private Optional<Map<String, String>> testLanguages;

Furthermore, setting ENV TEST_LANGUAGE_DE_ETR=Einfache Sprache does not yield an entry in the map at all.