Launcher Error: HttpClient.getOutputStream() NullPointerException ("this.http" is null)

What it looks like in the log

java.lang.RuntimeException: java.lang.NullPointerException: Cannot invoke "sun.net.www.http.HttpClient.getOutputStream()" because "this.http" is null

How to fix it

1. Disable your desktop environment's system-wide proxy (such as in KDE System Settings or GNOME Network Proxy) and restart the launcher to confirm the error stops.
2. Inside HMCL, go to Settings -> Download, switch the Proxy option away from Automatic/System Proxy, and either select No Proxy or manually configure your HTTP/SOCKS proxy address and port.
3. If you launch HMCL via a script or desktop entry on Linux, launch it with `-Djava.net.useSystemProxies=false` or clear conflicting `http_proxy`, `https_proxy`, and `all_proxy` environment variables.
4. Update to the latest official HMCL release instead of an outdated third-party or AUR snapshot build.

Check your own log