"Jump to definition" not working when source is provided as a source jar

[Shimin Guo]

I'm using a hand-generated ensime config. Everything else pretty much works, but I can't jump to definitions in source jars (other than scala-library and jdk) provided in reference-source-roots. With jdk, it's also a little strange in that M-. works, but M-, doesn't, with a message saying "No M-x tags-search or M-x tags-query-replace in progress" in the status bar. I'm using ensime with emacs and using the stable version. Any guidance on how to troubleshoot this issue, like how to get verbose logs, will be appreciated. Thanks!