Is the heads-up error display supposed to disappear on it’s own? I seem to remember it used to stay in the displayed position.

It pops up and then disappears right after.

Starting figwheel "lein figwheel" puts a randomly-named file in the root of my project. The contents seem to be using figwheel-sidecar and setting up my REPL. Someone thought these were winding up in my project root because some config file isn't telling Figwheel where to put it. Any ideas on the what and where of that setting?

Hmm.. this convo suggests is some invocation of "lein cljsbuild auto" that's the culprit. https://github.com/bhauman/lein-figwheel/issues/37

In the github issue for cljsbuild it's blamed on LEIN_FAST_TRAMPOLINE being set. The only thing I have in my lein profiles is cider. I wonder if that's setting environment variables. Ihttps://github.com/emezeske/lein-cljsbuild/issues/394

(in Linux command line) "unset LEIN_FAST_TRAMPOLINE" did the trick.

That's kind of in the chicken-waving department. I wish I knew what's going on.