--- type: Changed pr: 3173 --- **USER-GUIDE now documents installing for prerelease runtime editions** — adds a "Installing for Prerelease Editions (Next / Nightly / Insiders / Preview)" section with the `_CONFIG_DIR` env-var reference for every supported runtime. Resolves the discoverability gap behind requests like #3161 (Windsurf Next) without enumerating each prerelease channel as a separately tested runtime. Closes #3172.