Awesome, apparently #java checks for a supported "http" scheme in GVFS to decide whether it can open a browser, which is only supported when you install the `gvs-http` backend.
I'm pretty sure gvfs can open a browser without the backend, which seems to be mostly for downloading HTTP files.
jdk/src/java.desktop/unix/native/libawt_xawt/awt/gtk3_interface.c at b12daa41e23eaac2777a8f89ef279963d0e6f7a0 · openjdk/jdk

JDK main-line development https://openjdk.org/projects/jdk - openjdk/jdk

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