Actually, I'm using dictConfig to load config from json file. And yes, ext:// provides a way to load custom handler, but, as far as I see (https://github.com/jonashaag/cpython/blob/master/Lib/logging/config.py#L379-404), there is no possibility to specify custom parameters - terminator, for example. My proposal is to add this existing documented configurable parameter of standard logging handlers to constructors to make it configurable.

Also, there is a demand for configurable errors handler for encoding/decoding strings, but I think it should be another issue.

For now I'm just using derived classes in my project to achieve this functionality, is it really the right way (instead of patching stdlib)?