I spent almost three hours trying to run v0.30.0 on the "standard", Microsoft-branded VS Code binary on my Arch Linux with Elixir v1.19.2-otp-28 and Erlang v28.1.1 installed through ASDF, but whatever I did, the extension could not find my ASDF-installed Elixir. Ultimately, I tried setting ASDF_DIR and ASDF_DATA_DIR, and based on the shell script, I guess it's ASDF_DATA_DIR that did the trick (since ASDF_DIR doesn't get read for version greater than 0.16). I feel like this should be somewhere in "Troubleshooting" on the README. I can contribute a PR if necessary, just for the love of the next fellow going mad like me.