[pavog]

ModrinthAPIClient used Configuration::getDefaultConfiguration() when no configuration was passed. That is a process wide singleton, so all clients without an explicit configuration shared it:

• new ModrinthAPIClient("token-a") followed by new ModrinthAPIClient("token-b") made the first client send token-b
• creating a client without a token (new ModrinthAPIClient()) removed the token of every other client
• setUserAgent() changed the user agent of all clients

Every client now creates its own Configuration. The boolean query string format is still set on the default configuration as well, because the ObjectSerializer reads it from there.

Breaking changes

• Changes made to Configuration::getDefaultConfiguration() (e.g. setHost()) no longer apply to clients created without a configuration. Pass your own Configuration to the constructor instead.