fix(desktop): fall back to XWayland under WSL2

apps/desktop/README.md

@@ -22,3 +22,4 @@ The first build compiles GPUI from source and takes a while. The root `Cargo.loc
 - **macOS**: Xcode command line tools (Metal renderer).
 - **Windows**: no extra dependencies (Win32 + DirectWrite).
 - **Linux**: renders via Vulkan (Blade), windows via Wayland or X11 (both enabled by default). System packages (Debian/Ubuntu names): `libvulkan1` + working Vulkan drivers, `libwayland-dev`, `libx11-xcb-dev`, `libxkbcommon-x11-dev`, `libfontconfig-dev`, plus a C toolchain and `cmake`.
+- **WSL2/WSLg**: uses XWayland automatically when available. GPUI 0.2.2 requires `xdg_wm_base` v2–5, while WSLg advertises v1.

apps/desktop/src/main.rs

@@ -35,6 +35,26 @@ impl Render for Root {
 }
 
 fn main() {
+    #[cfg(target_os = "linux")]
+    {
+        let is_wsl = std::fs::read_to_string("/proc/sys/kernel/osrelease")
+            .is_ok_and(|release| release.to_ascii_lowercase().contains("microsoft"));
+        let x11_configured =
+            std::env::var_os("DISPLAY").is_some_and(|display| !display.is_empty());
+        let wayland_configured =
+            std::env::var_os("WAYLAND_DISPLAY").is_some_and(|display| !display.is_empty());
+
+        if is_wsl && x11_configured && wayland_configured {
+            // GPUI 0.2.2 requires xdg_wm_base v2+, while current WSLg advertises v1 and panics.
+            // Safety: this is the first statement in `main`, before GPUI or anything
+            // else has spawned a thread. No other thread exists yet, so keep this
+            // block first if anything is added above it.
+            unsafe {
+                std::env::remove_var("WAYLAND_DISPLAY");
+            }
+        }
+    }
+
     Application::new().run(|cx: &mut App| {
         let bounds = Bounds::centered(None, size(px(960.), px(600.)), cx);
         cx.open_window(