what the policy on var?

[SimonCropp]

currently there are

places where type is apparent where var is not use

List<IOperationConfig> operationConfigReaders = new List<IOperationConfig>(componentManager.OfType<IOperationConfig>());

places where type is apparent where var is used

var process = new Process()

places where type is not apparent where var is used

var installer = installerFactory.CreateInstaller(settings, packagesFolder);

which also produce a warning

places where target typed new is used instead of var

TokenTrie trie = new();

So what is the preference?