From 697b82e85d0d2ad63c0995bd90b73a7ef62fee3b Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:40:11 +0200
Subject: [PATCH 1/7] Read the heat pass's depth through a nearest sampler, as
 WebGL2 reads it as 0 otherwise

---
 crates/client/src/heat.rs   | 11 ++++++++++-
 crates/client/src/heat.wesl | 20 +++++++++-----------
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/crates/client/src/heat.rs b/crates/client/src/heat.rs
index 119d1ae..c4c497b 100644
--- a/crates/client/src/heat.rs
+++ b/crates/client/src/heat.rs
@@ -130,7 +130,8 @@ impl Plugin for HeatPlugin {
     }
 }
 
-/// The pass reads the depth buffer of the camera that has it.
+/// The pass reads the depth buffer of the camera that has it. (WebGL2 could not read a
+/// multisampled one: a browser has no msaa, see `config.rs`.)
 fn readable_depth(add: On<Add<HeatWarp>>, mut cameras: Query<&mut Camera3d>) {
     if let Ok(mut camera) = cameras.get_mut(add.entity) {
         let usages = TextureUsages::from(camera.depth_texture_usages);
@@ -290,6 +291,8 @@ struct HeatPipeline {
     /// With the depth buffer as it is without multisampling, and as it is with.
     layouts: [BindGroupLayoutDescriptor; 2],
     sampler: Sampler,
+    /// Nearest, for the depth buffer without multisampling (see `heat.wesl`).
+    depth_sampler: Sampler,
     shader: Handle<Shader>,
     vertex: FullscreenShader,
     /// By the format of the picture and its samples.
@@ -312,6 +315,7 @@ fn init_pipeline(
                     sampler(SamplerBindingType::Filtering),
                     uniform_buffer::<HeatWarp>(true),
                     depth,
+                    sampler(SamplerBindingType::NonFiltering),
                 ),
             ),
         )
@@ -330,6 +334,10 @@ fn init_pipeline(
             ),
         ],
         sampler: render_device.create_sampler(&SamplerDescriptor::default()),
+        depth_sampler: render_device.create_sampler(&SamplerDescriptor {
+            label: Some("heat_warp_depth_sampler"),
+            ..default()
+        }),
         shader: asset_server.load(concat!("embedded://", env!("CARGO_PKG_NAME"), "/heat.wesl")),
         vertex: fullscreen_shader.clone(),
         pipelines: HashMap::new(),
@@ -430,6 +438,7 @@ fn pass(
             &pipeline.sampler,
             binding,
             depth_view,
+            &pipeline.depth_sampler,
         )),
     );
     let mut render_pass = ctx
diff --git a/crates/client/src/heat.wesl b/crates/client/src/heat.wesl
index 8b6bbfd..f45c317 100644
--- a/crates/client/src/heat.wesl
+++ b/crates/client/src/heat.wesl
@@ -20,9 +20,12 @@ struct HeatWarp {
 @if(MULTISAMPLED)
 @group(0) @binding(3) var depth_texture: texture_depth_multisampled_2d;
 // A float texture rather than a depth one (its depth in `r`), as WebGL2 cannot `textureLoad` a
-// depth texture.
+// depth texture. It is read through a sampler: WebGL2 reads a depth texture as 0 when its own
+// filtering is linear, which it is (wgpu cannot set it), and the sampler's nearest overrides that.
 @if(!MULTISAMPLED)
 @group(0) @binding(3) var depth_texture: texture_2d<f32>;
+@if(!MULTISAMPLED)
+@group(0) @binding(4) var depth_sampler: sampler;
 
 struct Input {
     @builtin(position) position: vec4<f32>,
@@ -49,21 +52,16 @@ fn lens_depth(lens: u32) -> f32 {
     return heat.points[lens * PER_LENS + 1u].w;
 }
 
-// The depth at the texel `at`: the float texture has it in `r`.
+// The scene's depth at uv (the first sample, if it is multisampled).
 @if(MULTISAMPLED)
-fn load_depth(at: vec2<i32>) -> f32 {
+fn depth_at(uv: vec2<f32>) -> f32 {
+    let size = vec2<i32>(textureDimensions(depth_texture));
+    let at = clamp(vec2<i32>(uv * vec2<f32>(size)), vec2<i32>(0), size - 1);
     return textureLoad(depth_texture, at, 0);
 }
 @if(!MULTISAMPLED)
-fn load_depth(at: vec2<i32>) -> f32 {
-    return textureLoad(depth_texture, at, 0).r;
-}
-
-// The scene's depth at uv (the first sample, if it is multisampled).
 fn depth_at(uv: vec2<f32>) -> f32 {
-    let size = vec2<i32>(textureDimensions(depth_texture));
-    let at = clamp(vec2<i32>(uv * vec2<f32>(size)), vec2<i32>(0), size - 1);
-    return load_depth(at);
+    return textureSampleLevel(depth_texture, depth_sampler, uv, 0.0).r;
 }
 
 // Whether what is drawn at uv is in front of the lens, drawn after it in retail.

From 40090fa324f83fff3ef4077d4e8bca146cbafd0d Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:40:11 +0200
Subject: [PATCH 2/7] Force MSAA off in the browser, where the heat pass cannot
 read a multisampled depth buffer

---
 crates/client/src/config.rs  | 11 +++++++++--
 crates/client/src/suggest.rs |  2 ++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/crates/client/src/config.rs b/crates/client/src/config.rs
index 206d3f4..41d8f0e 100644
--- a/crates/client/src/config.rs
+++ b/crates/client/src/config.rs
@@ -27,7 +27,9 @@
 //!   [`MAX_RELAYS`]; it holds from the next lobby), and `/net relay clear` to drop them all
 //!
 //! A browser has no vsync or fps-max, and no relay-only: it paces the frames to the display
-//! itself, and reaches the others through the relay only.
+//! itself, and reaches the others through the relay only. Nor has it msaa: the heat shimmer and
+//! the warpball's glow (`heat.rs`) read the depth buffer, which WebGL2 cannot when it is
+//! multisampled.
 //!
 //! The last character driven is kept too, and is the one the client starts with, and the
 //! keyboard's driving keys, which the pause menu's Controls change (`controls.rs`), and whether
@@ -122,6 +124,9 @@ impl Default for Config {
 impl Config {
     /// The multisampling of the cameras.
     pub fn msaa(&self) -> Msaa {
+        if cfg!(target_arch = "wasm32") {
+            return Msaa::Off;
+        }
         match self.msaa {
             2 => Msaa::Sample2,
             4 => Msaa::Sample4,
@@ -289,7 +294,6 @@ const USAGE: &str = "Usage: /config set nickname [name, up to 12 characters]\n\
     /config set volume music|sfx|voice <0-100>";
 #[cfg(target_arch = "wasm32")]
 const USAGE: &str = "Usage: /config set nickname [name, up to 12 characters]\n\
-    /config set msaa off|2|4\n\
     /config set shader-effects on|off\n\
     /config set render-scale <0.25 to 1>\n\
     /config set volume music|sfx|voice <0-100>";
@@ -303,6 +307,9 @@ impl Setting {
                 "vsync" | "fps-max" => {
                     return Err("In a browser, the browser sets the frame rate".into());
                 }
+                "msaa" => {
+                    return Err("In a browser, anti-aliasing is off for the heat shimmer".into());
+                }
                 _ => {}
             }
         }
diff --git a/crates/client/src/suggest.rs b/crates/client/src/suggest.rs
index e1d3f14..4aeb3d1 100644
--- a/crates/client/src/suggest.rs
+++ b/crates/client/src/suggest.rs
@@ -309,6 +309,8 @@ pub(crate) const COMMANDS: &[Spec] = &[
                     "How much of the resolution to draw",
                     "<0.25 to 1>",
                 ),
+                // (A browser has no msaa either, see `config.rs`.)
+                #[cfg(not(target_arch = "wasm32"))]
                 node(
                     "msaa",
                     "Anti-aliasing samples of the cameras",

From ebf8bf5b19ac0c2c52483958d0000acdb59a02bf Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:40:11 +0200
Subject: [PATCH 3/7] Cut the lighting out of Bevy's StandardMaterial shader,
 which Firefox on macOS takes ~8 s per pipeline to link

---
 crates/client/src/main.rs  |  2 ++
 crates/client/src/unlit.rs | 69 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 crates/client/src/unlit.rs

diff --git a/crates/client/src/main.rs b/crates/client/src/main.rs
index 848406a..328e785 100644
--- a/crates/client/src/main.rs
+++ b/crates/client/src/main.rs
@@ -80,6 +80,7 @@ mod suggest;
 mod toast;
 mod track_picture;
 mod tracker;
+mod unlit;
 mod version;
 mod weapon;
 mod weather;
@@ -247,6 +248,7 @@ fn main() {
         .add_plugins(sky::SkyPlugin)
         .add_plugins(drop_map::DropMapPlugin)
         .add_plugins(MaterialPlugin::<SubtractMaterial>::default())
+        .add_plugins(unlit::UnlitPlugin)
         .insert_resource(Time::<Fixed>::from_hz(GAME_TICK_HZ))
         .add_systems(
             FixedUpdate,
diff --git a/crates/client/src/unlit.rs b/crates/client/src/unlit.rs
new file mode 100644
index 0000000..99e3528
--- /dev/null
+++ b/crates/client/src/unlit.rs
@@ -0,0 +1,69 @@
+//! Every material of ours is unlit, but Bevy's `StandardMaterial` draws through a fragment shader
+//! with all of Bevy's lighting in it: `unlit` is a flag the shader reads as it runs, not one it is
+//! compiled without. On WebGL2 the lights are a uniform array of 204 of them, which Firefox on
+//! macOS (through Apple's OpenGL) takes about 8 s to link, for each of the mesh pipelines: most of
+//! a minute before the first frame. So the lighting is cut out of Bevy's shader as it is loaded,
+//! leaving what it does for an unlit material. A lit material, or a Bevy light, would be drawn
+//! unlit.
+
+use bevy::asset::AssetEventSystems;
+use bevy::prelude::*;
+use bevy::shader::{Shader, Source};
+
+/// Where Bevy keeps the shader (`bevy_pbr`'s `load_shader_library!`).
+const PATH: &str = "embedded://bevy_pbr/render/pbr.wesl";
+
+/// The choice between the lit and the unlit color in Bevy's shader, and the unlit one alone.
+const LIGHTING: &str =
+    "    if (pbr_input.material.flags & STANDARD_MATERIAL_FLAGS_UNLIT_BIT) == 0u {
+        out.color = apply_pbr_lighting(pbr_input);
+    } else {
+        out.color = pbr_input.material.base_color;
+    }
+";
+const UNLIT: &str = "    out.color = pbr_input.material.base_color;
+";
+
+pub struct UnlitPlugin;
+
+impl Plugin for UnlitPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(Startup, check)
+            .add_systems(PostUpdate, cut_lighting.after(AssetEventSystems));
+    }
+}
+
+/// Tells if Bevy no longer has the shader where it is looked for (after an upgrade).
+fn check(asset_server: Res<AssetServer>) {
+    if asset_server.get_handle::<Shader>(PATH).is_none() {
+        warn!("{PATH} is not loaded: the meshes are drawn with Bevy's lighting in their shader");
+    }
+}
+
+/// Cuts the lighting in the frame the shader is loaded, before the render world takes it
+/// (`extract_shaders` reads it as it is then). Untracked, as a change would make the render world
+/// build its pipelines again. Left as it is if Bevy's shader no longer reads as [`LIGHTING`].
+fn cut_lighting(
+    mut events: MessageReader<AssetEvent<Shader>>,
+    mut shaders: ResMut<Assets<Shader>>,
+) {
+    for event in events.read() {
+        let AssetEvent::Added { id } = event else {
+            continue;
+        };
+        let Some(shader) = shaders.get_mut_untracked(*id) else {
+            continue;
+        };
+        if shader.path != PATH {
+            continue;
+        }
+        let Source::Wesl(source) = &shader.source else {
+            continue;
+        };
+        if source.matches(LIGHTING).count() != 1 {
+            warn!("{PATH} has changed: the meshes are drawn with Bevy's lighting in their shader");
+            continue;
+        }
+        shader.source = Source::Wesl(source.replace(LIGHTING, UNLIT).into());
+    }
+}

From d7fb2a83104769a0d2d6479a5de5aef6a2c6d3dc Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:44:19 +0200
Subject: [PATCH 4/7] Set an unreadable config aside, and offer a restart with
 default settings after a crash

---
 crates/client/src/config.rs | 21 +++++++++++++++++++++
 crates/client/src/web.rs    |  4 ++++
 web/play.html               | 24 ++++++++++++++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/crates/client/src/config.rs b/crates/client/src/config.rs
index 41d8f0e..d9d1876 100644
--- a/crates/client/src/config.rs
+++ b/crates/client/src/config.rs
@@ -195,6 +195,23 @@ fn write(text: &str) -> Result<(), String> {
     }
 }
 
+/// Moves the settings to where they are no longer read, nor overwritten by the next ones saved,
+/// and says where.
+#[cfg(not(target_arch = "wasm32"))]
+fn set_aside() -> Result<String, String> {
+    let to = path().with_extension("json.broken");
+    std::fs::rename(path(), &to).map_err(|e| format!("Could not move {}: {e}", place()))?;
+    Ok(to.display().to_string())
+}
+
+#[cfg(target_arch = "wasm32")]
+fn set_aside() -> Result<String, String> {
+    match crate::web::set_config_aside() {
+        None => Ok("ctr-rs.config.broken in the browser's storage".to_string()),
+        Some(e) => Err(format!("Could not move the settings: {e}")),
+    }
+}
+
 impl Config {
     /// What is kept; the defaults if there is nothing or it cannot be read (it is told of).
     pub fn load() -> Config {
@@ -224,6 +241,10 @@ impl Config {
             }
             Err(e) => {
                 eprintln!("{}: {e}", place());
+                match set_aside() {
+                    Ok(to) => eprintln!("The defaults are used: what could not be read is in {to}"),
+                    Err(why) => eprintln!("{why}"),
+                }
                 Config::default()
             }
         }
diff --git a/crates/client/src/web.rs b/crates/client/src/web.rs
index f4f625b..f6a4844 100644
--- a/crates/client/src/web.rs
+++ b/crates/client/src/web.rs
@@ -80,6 +80,10 @@ extern "C" {
     #[wasm_bindgen(js_namespace = window, js_name = ctrSaveConfig)]
     pub fn save_config(text: &str) -> Option<String>;
 
+    /// Moves the settings to where they are no longer read; what went wrong if the page could not.
+    #[wasm_bindgen(js_namespace = window, js_name = ctrSetConfigAside)]
+    pub fn set_config_aside() -> Option<String>;
+
     /// The maps the page keeps, as the bytes of their files (`Uint8Array`s), once.
     #[wasm_bindgen(js_namespace = window, js_name = ctrTakeMaps)]
     fn take_saved_maps() -> js_sys::Array;
diff --git a/web/play.html b/web/play.html
index da03f64..6923221 100644
--- a/web/play.html
+++ b/web/play.html
@@ -400,6 +400,21 @@ <h1><a href="../">CTR-RS</a></h1>
     return String(e);
   }
 };
+// Moves the settings to where the game no longer reads them (and the next ones do not overwrite
+// them): a game they make crash, or cannot read, starts again with the defaults.
+const CONFIG_ASIDE = `${CONFIG}.broken`;
+function setConfigAside() {
+  try {
+    const text = localStorage.getItem(CONFIG);
+    if (text === null) return null;
+    localStorage.setItem(CONFIG_ASIDE, text);
+    localStorage.removeItem(CONFIG);
+    return null;
+  } catch (e) {
+    return String(e);
+  }
+}
+window.ctrSetConfigAside = setConfigAside;
 
 // The game reads the image from here (a wasm program's memory never shrinks, so it is not copied
 // in), and lets go of it once it has taken what it needs.
@@ -472,8 +487,17 @@ <h1><a href="../">CTR-RS</a></h1>
   document.getElementById("detail").textContent = message;
   document.getElementById("detail").hidden = false;
   document.getElementById("note").hidden = true;
+  let kept = false;
+  try {
+    kept = localStorage.getItem(CONFIG) !== null;
+  } catch {}
   offer(starting ? "The game could not start" : "The game crashed", [
     ["Restart", () => location.reload()],
+    ...(kept ? [["Restart with default settings", () => {
+      const e = setConfigAside();
+      if (e !== null) console.warn(`could not set the settings aside: ${e}`);
+      location.reload();
+    }]] : []),
     ...(starting ? [["Pick another .bin", () => forget().then(() => location.reload())]] : []),
     ["Copy the error", copyCrash],
   ]);

From 8b9383003b9ef2f0e6019fd620261516bf1598ac Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:56:00 +0200
Subject: [PATCH 5/7] Fetch and compile the wasm while the disc is picked and
 read

---
 web/play.html | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/web/play.html b/web/play.html
index 6923221..cbbe1ff 100644
--- a/web/play.html
+++ b/web/play.html
@@ -192,6 +192,15 @@ <h1><a href="../">CTR-RS</a></h1>
 <script type="module">
 import init from "./client.js";
 
+// The game's code is fetched and compiled from the start, while the player picks the disc and it is
+// read; `init` falls back to fetching it itself if that fails.
+const compiled = WebAssembly.compileStreaming(fetch(new URL("client_bg.wasm", import.meta.url))).catch(
+  (e) => {
+    console.warn(`could not compile the game ahead: ${e}`);
+    return null;
+  },
+);
+
 const drop = document.getElementById("drop");
 const status = document.getElementById("status");
 const menu = document.getElementById("menu");
@@ -459,7 +468,8 @@ <h1><a href="../">CTR-RS</a></h1>
   });
   status.textContent = "Starting";
   try {
-    await init();
+    const module = await compiled;
+    await init(module === null ? undefined : { module_or_path: module });
   } catch (e) {
     // winit hands the event loop to the browser by throwing.
     if (!String(e).includes("Using exceptions for control flow")) {

From 612d0084790f043cd7742e1812f4352c8fc0f02f Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 00:56:00 +0200
Subject: [PATCH 6/7] Add tell!, which in a browser goes to the console where
 eprintln! goes nowhere

---
 crates/client/src/config.rs | 12 ++++++------
 crates/client/src/disc.rs   | 16 ++++++++--------
 crates/client/src/main.rs   | 10 ++++++++++
 crates/client/src/maps.rs   | 22 ++++++++++------------
 crates/client/src/web.rs    |  4 ++++
 5 files changed, 38 insertions(+), 26 deletions(-)

diff --git a/crates/client/src/config.rs b/crates/client/src/config.rs
index d9d1876..79b0bfd 100644
--- a/crates/client/src/config.rs
+++ b/crates/client/src/config.rs
@@ -219,7 +219,7 @@ impl Config {
             Ok(Some(text)) => text,
             Ok(None) => return Config::default(),
             Err(why) => {
-                eprintln!("{why}");
+                tell!("{why}");
                 return Config::default();
             }
         };
@@ -235,15 +235,15 @@ impl Config {
                 }
                 config.relays = relays;
                 for cup in config.cups.take_invalid() {
-                    eprintln!("{}: dropped the cup {cup:?}", place());
+                    tell!("{}: dropped the cup {cup:?}", place());
                 }
                 config
             }
             Err(e) => {
-                eprintln!("{}: {e}", place());
+                tell!("{}: {e}", place());
                 match set_aside() {
-                    Ok(to) => eprintln!("The defaults are used: what could not be read is in {to}"),
-                    Err(why) => eprintln!("{why}"),
+                    Ok(to) => tell!("The defaults are used: what could not be read is in {to}"),
+                    Err(why) => tell!("{why}"),
                 }
                 Config::default()
             }
@@ -261,7 +261,7 @@ impl Config {
         if self.character != Some(character) {
             self.character = Some(character);
             if let Err(why) = self.save() {
-                eprintln!("{why}");
+                tell!("{why}");
             }
         }
     }
diff --git a/crates/client/src/disc.rs b/crates/client/src/disc.rs
index 4e0e4fa..00df60e 100644
--- a/crates/client/src/disc.rs
+++ b/crates/client/src/disc.rs
@@ -43,8 +43,8 @@ pub fn prepare() {
     // go of the image (`web::release_disc`).
     if cfg!(target_arch = "wasm32") {
         match source.hold() {
-            Ok(size) => eprintln!("Took {} MiB from the disc", size >> 20),
-            Err(e) => eprintln!("Could not take the files of the disc: {e}"),
+            Ok(size) => tell!("Took {} MiB from the disc", size >> 20),
+            Err(e) => tell!("Could not take the files of the disc: {e}"),
         }
         return;
     }
@@ -54,18 +54,18 @@ pub fn prepare() {
         Check::Stale(why) => format!("making the files of the disc again: {why}"),
         Check::Missing(needs) => format!("making {} more files of the disc", needs.len()),
     };
-    eprintln!("{}...", why);
+    tell!("{}...", why);
     let mut told = 0;
     let made = source.prepare(|done, of| {
         let tenth = if of == 0 { 10 } else { done * 10 / of };
         if tenth > told {
             told = tenth;
-            eprintln!("  {}%", tenth * 10);
+            tell!("  {}%", tenth * 10);
         }
     });
     match made {
-        Ok(made) => eprintln!("Made {made} files in {}", paths::disc().display()),
-        Err(e) => eprintln!("Could not make the files of the disc: {e}"),
+        Ok(made) => tell!("Made {made} files in {}", paths::disc().display()),
+        Err(e) => tell!("Could not make the files of the disc: {e}"),
     }
 }
 
@@ -84,12 +84,12 @@ pub fn locate(config: &mut Config) {
         let picked = ask()?;
         config.iso = Some(picked.clone());
         if let Err(why) = config.save() {
-            eprintln!("{why}");
+            tell!("{why}");
         }
         Some(picked)
     });
     let Some(path) = found else {
-        eprintln!(
+        tell!(
             "No Crash Team Racing (USA) disc image. Set CTR_BIN to its path, or \"iso\" in {}\n\
              (it is read once, to make the files of the game in {})",
             crate::paths::config_file().display(),
diff --git a/crates/client/src/main.rs b/crates/client/src/main.rs
index 328e785..7c30254 100644
--- a/crates/client/src/main.rs
+++ b/crates/client/src/main.rs
@@ -14,6 +14,16 @@
 // Bevy systems take their parameters and `Query` filters as types, so both lints fire on them.
 #![allow(clippy::too_many_arguments, clippy::type_complexity)]
 
+/// Like `eprintln!`, which in a browser goes nowhere: there it goes to the console.
+macro_rules! tell {
+    ($($arg:tt)*) => {{
+        #[cfg(not(target_arch = "wasm32"))]
+        eprintln!($($arg)*);
+        #[cfg(target_arch = "wasm32")]
+        crate::web::console_warn(&format!($($arg)*));
+    }};
+}
+
 mod about;
 mod accordion;
 mod animation;
diff --git a/crates/client/src/maps.rs b/crates/client/src/maps.rs
index 142cd40..a3b1c92 100644
--- a/crates/client/src/maps.rs
+++ b/crates/client/src/maps.rs
@@ -68,7 +68,7 @@ pub fn load() {
                 let (mut id, hash, map) = match read {
                     Ok(read) => read,
                     Err(e) => {
-                        eprintln!("{}: {e}", path.display());
+                        tell!("{}: {e}", path.display());
                         continue;
                     }
                 };
@@ -78,14 +78,14 @@ pub fn load() {
                     } else {
                         "a custom track cannot be named for one of the game's tracks"
                     };
-                    eprintln!("{}: {why}", path.display());
+                    tell!("{}: {why}", path.display());
                     continue;
                 }
                 if builtins {
                     match builtin::level_of(&map.name) {
                         Some(level) => id = level.0,
                         None => {
-                            eprintln!("{}: not one of the game's tracks", path.display());
+                            tell!("{}: not one of the game's tracks", path.display());
                             continue;
                         }
                     }
@@ -103,7 +103,7 @@ pub fn load() {
         for bytes in crate::web::take_maps() {
             match Map::from_bytes(&bytes).and_then(|m| Ok((m.id()?, m.hash()?, m))) {
                 Ok((_, _, map)) if builtin::is_builtin_name(&map.name) => {
-                    eprintln!(
+                    tell!(
                         "{}: a custom track cannot be named for one of the game's tracks",
                         map.name
                     );
@@ -114,7 +114,7 @@ pub fn load() {
                     file: File::Held(bytes),
                     map: Box::leak(Box::new(map)),
                 }),
-                Err(e) => eprintln!("A kept track: {e}"),
+                Err(e) => tell!("A kept track: {e}"),
             }
         }
         maps.sort_by(|a, b| a.map.name.cmp(&b.map.name));
@@ -321,15 +321,13 @@ pub fn make_builtins() {
         return;
     }
     let Some(image) = crate::disc::image() else {
-        eprintln!(
-            "The game's own tracks are missing, and there is no disc image to make them from"
-        );
+        tell!("The game's own tracks are missing, and there is no disc image to make them from");
         return;
     };
-    eprintln!("Making the game's own tracks from the disc (this is done once)...");
+    tell!("Making the game's own tracks from the disc (this is done once)...");
     match map::builtin::export(&image, &dir) {
-        Ok(made) => eprintln!("Made {made} tracks in {}", dir.display()),
-        Err(e) => eprintln!("Could not make the game's own tracks: {e}"),
+        Ok(made) => tell!("Made {made} tracks in {}", dir.display()),
+        Err(e) => tell!("Could not make the game's own tracks: {e}"),
     }
 }
 
@@ -343,7 +341,7 @@ pub fn make_builtins() {
     let made = match builtin::make_all(&image) {
         Ok(made) => made,
         Err(e) => {
-            eprintln!("Could not make the game's own tracks: {e}");
+            tell!("Could not make the game's own tracks: {e}");
             return;
         }
     };
diff --git a/crates/client/src/web.rs b/crates/client/src/web.rs
index f6a4844..87facb2 100644
--- a/crates/client/src/web.rs
+++ b/crates/client/src/web.rs
@@ -80,6 +80,10 @@ extern "C" {
     #[wasm_bindgen(js_namespace = window, js_name = ctrSaveConfig)]
     pub fn save_config(text: &str) -> Option<String>;
 
+    /// `console.warn`, for what a native build prints (`tell!`).
+    #[wasm_bindgen(js_namespace = console, js_name = warn)]
+    pub fn console_warn(text: &str);
+
     /// Moves the settings to where they are no longer read; what went wrong if the page could not.
     #[wasm_bindgen(js_namespace = window, js_name = ctrSetConfigAside)]
     pub fn set_config_aside() -> Option<String>;

From 5a6376fde96e979510ec2407b9078ceccfcb46f4 Mon Sep 17 00:00:00 2001
From: Otto Pirttimaa <otto.pirttimaa@gmail.com>
Date: Wed, 4 Nov 2026 01:06:55 +0200
Subject: [PATCH 7/7] Build the shipped wasm without the dev features, as cargo
 dist does

---
 web/build.sh | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/web/build.sh b/web/build.sh
index 8606afc..0170e12 100755
--- a/web/build.sh
+++ b/web/build.sh
@@ -20,12 +20,14 @@ dev) dir=debug ;;
 *) dir="$profile" ;;
 esac
 
-cargo build -p client --target wasm32-unknown-unknown --profile "$profile"
 if [ "$profile" = dist ]; then
+    features=--no-default-features
     names=--remove-name-section
 else
+    features=
     names=
 fi
+cargo build -p client --target wasm32-unknown-unknown --profile "$profile" $features
 wasm-bindgen --target web --no-typescript $names --out-dir target/web/play --out-name client \
     "target/wasm32-unknown-unknown/$dir/client.wasm"
 if [ "$profile" = dist ]; then