Is it possible to ask Meltano not to delete config file that was used to invoke plugin? I would like to inspect it, to try to find an issue with configuration.

I think the

--dump config

option is what you're looking for.

Yes. I thought so too. But in case of mappers it prints

null

For discussion: Feature Idea: CLI `--cleanup=false` option to retain temp config files after execution · Discussion #6441 · meltano/meltano (github.com)