fix multithread

web/Cargo.toml

@@ -32,7 +32,7 @@ console_log = "1.0"
 wasm-bindgen = "0.2"
 wasm-bindgen-futures = "0.4"
 js-sys = "0.3"
-web-sys = { version = "0.3", features = ["Window", "Performance", "Location"] }
+web-sys = { version = "0.3", features = ["Window", "Performance"] }
 universal-time = { git = "https://github.com/shadowylab/universal-time" }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]

web/rust-toolchain.toml

@@ -1,4 +1,4 @@
 [toolchain]
 channel = "nightly"
-components = ["rustfmt", "clippy", "rust-src"]
+components = ["rustfmt", "clippy"]
 targets = ["wasm32-unknown-unknown"]

web/script/build-wasm.sh

@@ -37,12 +37,14 @@ fi
 
 # Step 1: Build WASM
 #
-# Target features and link args (atomics, shared memory, TLS exports) come
+# Single-threaded build: `+bulk-memory` only. The multithreaded web backend
-# from `web/.cargo/config.toml`, which also enables `-Z build-std` so std is
+# is disabled in `web/src/lib.rs` (gpui's wasm workers freeze their JS event
-# rebuilt with atomics support.
+# loop in `Atomics.wait`, which breaks nostr-sdk's spawn_local-driven client
+# and the WebSocket transport), so no atomics/shared-memory flags here.
 echo -e "${GREEN}Step 1: Building WASM...${NC}"
 cd "$PROJECT_ROOT"
 export CARGO_TARGET_DIR="$PROJECT_ROOT/target"
+RUSTFLAGS='-C target-feature=+bulk-memory -C link-arg=--max-memory=4294967296' \
 cargo build --target wasm32-unknown-unknown $RELEASE_FLAG
 
 # Determine the build directory

web/src/lib.rs

@@ -31,30 +31,6 @@ impl MonotonicClock for CustomTimeProvider {
 
 define_time_provider!(CustomTimeProvider);
 
-/// Returns the preferred WebGPU/WebGL backend, selected with
-/// `?backend=webgpu` / `?backend=webgl` in the page URL.
-#[cfg(target_family = "wasm")]
-fn requested_backend() -> gpui_platform::WebBackendPreference {
-    let search = web_sys::window()
-        .and_then(|window| window.location().search().ok())
-        .unwrap_or_default();
-    if search
-        .trim_start_matches('?')
-        .split('&')
-        .any(|parameter| parameter == "backend=webgpu")
-    {
-        gpui_platform::WebBackendPreference::WebGpu
-    } else if search
-        .trim_start_matches('?')
-        .split('&')
-        .any(|parameter| parameter == "backend=webgl")
-    {
-        gpui_platform::WebBackendPreference::WebGl
-    } else {
-        gpui_platform::WebBackendPreference::Auto
-    }
-}
-
 thread_local! {
     static APPLICATION: RefCell<Option<ApplicationHandle>> = const { RefCell::new(None) };
 }
@@ -120,10 +96,13 @@ pub async fn run() -> Result<(), JsValue> {
         // immediately instead of waiting for a repaint.
         assets.preload().await;
 
-        // Multithreaded web: background work (image decoding, network
+        // NOTE: the multithreaded web backend (application_with_web_backend)
-        // fetches, CPU-heavy tasks) runs on real worker threads instead of
+        // cannot host this app's backend. gpui's wasm background workers
-        // the main thread, so the UI stays responsive.
+        // block on `Atomics.wait` while idle, freezing their JS event loop,
-        gpui_platform::application_with_web_backend(requested_backend()).with_assets(assets)
+        // so `spawn_local`-driven tasks (nostr-sdk's client actor, the
+        // WebSocket transport) and fetch promises never make progress on a
+        // worker thread. Everything must run on the main thread.
+        gpui_platform::single_threaded_web().with_assets(assets)
     };
 
     let launch = move |cx: &mut App| {