fix(locale): stabilize web options

Embed debug locales and expand the WebAssembly stack so modal construction remains responsive. Keep the Options scrollbar in its own lane and refine Turkish CAD terminology.

src/i18n.rs

@@ -7,8 +7,8 @@ use i18n_embed::DesktopLanguageRequester;
 #[cfg(target_arch = "wasm32")]
 use i18n_embed::WebLanguageRequester;
 use rust_embed::RustEmbed;
-use std::borrow::Cow;
 use serde::{Deserialize, Serialize};
+use std::borrow::Cow;
 use std::sync::OnceLock;
 
 #[path = "locale_catalog.rs"]
@@ -69,11 +69,9 @@ impl Language {
             Language::ZhCn => vec!["zh-CN".parse().expect("valid locale")],
         }
     }
-}
 
-impl std::fmt::Display for Language {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let label = match self {
+    pub fn label(self) -> String {
+        match self {
             Language::System => crate::tr!("language-system"),
             Language::EnUs => crate::tr!("language-english"),
             Language::TrTr => crate::tr!("language-turkish"),
@@ -83,16 +81,36 @@ impl std::fmt::Display for Language {
             Language::HiIn => crate::tr!("language-hindi"),
             Language::RuRu => crate::tr!("language-russian"),
             Language::ZhCn => crate::tr!("language-chinese-simplified"),
-        };
+        }
+    }
+}
+
+impl std::fmt::Display for Language {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let label = self.label();
         f.write_str(&label)
     }
 }
 
 fn system_languages() -> Vec<i18n_embed::unic_langid::LanguageIdentifier> {
     #[cfg(target_arch = "wasm32")]
-    let requested = WebLanguageRequester::requested_languages();
+    let mut requested = WebLanguageRequester::requested_languages();
     #[cfg(not(target_arch = "wasm32"))]
     let requested = DesktopLanguageRequester::requested_languages();
+
+    // `navigator.languages` may be empty in privacy-restricted browser
+    // contexts. The singular preference is still exposed by mainstream
+    // browsers, so keep it as the first fallback before English.
+    #[cfg(target_arch = "wasm32")]
+    if requested.is_empty() {
+        if let Some(language) = web_sys::window()
+            .and_then(|window| window.navigator().language())
+            .and_then(|language| language.parse().ok())
+        {
+            requested.push(language);
+        }
+    }
+
     requested
 }
 
@@ -104,7 +122,17 @@ fn load_language(
     if requested.is_empty() {
         requested.push(loader.fallback_language().clone());
     }
-    i18n_embed::select(loader, &Localizations, &requested).map(|_| ())
+    let selected = i18n_embed::select(loader, &Localizations, &requested)?;
+    #[cfg(target_arch = "wasm32")]
+    if let Some(language) = selected.first() {
+        if let Some(root) = web_sys::window()
+            .and_then(|window| window.document())
+            .and_then(|document| document.document_element())
+        {
+            let _ = root.set_attribute("lang", &language.to_string());
+        }
+    }
+    Ok(())
 }
 
 pub fn loader() -> &'static FluentLanguageLoader {

src/ui/modal.rs

@@ -322,16 +322,7 @@ pub fn modal<'a>(
     // The first stack layer dictates its intrinsic size. Its top spacer reserves
     // room for the title, while the actual title bar and resize grip overlay it
     // without influencing the modal dimensions.
-    // Iced draws vertical scrollbars inside a scrollable's bounds. Reserve a
-    // shared end gutter at the modal boundary so a scrollbar cannot cover the
-    // last control column in Options or any other dialog.
-    let measured_content = container(sensor(content).on_resize(Message::ModalContentResized))
-        .padding(Padding {
-            top: 0.0,
-            right: 12.0,
-            bottom: 0.0,
-            left: 0.0,
-        });
+    let measured_content = sensor(content).on_resize(Message::ModalContentResized);
     let body_base = column![
         Space::new().height(Length::Fixed(24.0)),
         measured_content,

src/ui/window/options.rs

@@ -7,17 +7,14 @@ use iced::{Background, Border, Element, Theme};
 use std::fmt;
 
 #[derive(Clone, Debug, PartialEq, Eq)]
-struct ThemeChoice(String);
+struct Labelled<T> {
+    value: T,
+    label: String,
+}
 
-impl fmt::Display for ThemeChoice {
+impl<T> fmt::Display for Labelled<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let label = match self.0.as_str() {
-            "Light" => crate::t!("Light"),
-            "Dark" => crate::t!("Dark"),
-            "Custom" => crate::t!("Custom"),
-            _ => std::borrow::Cow::Borrowed(self.0.as_str()),
-        };
-        f.write_str(label.as_ref())
+        f.write_str(&self.label)
     }
 }
 
@@ -37,9 +34,32 @@ pub fn view_window<'a>(
         .iter()
         .map(ToString::to_string)
         .chain(std::iter::once("Custom".to_string()))
-        .map(ThemeChoice)
+        .map(|value| Labelled {
+            label: match value.as_str() {
+                "Light" => crate::t!("Light").into_owned(),
+                "Dark" => crate::t!("Dark").into_owned(),
+                "Custom" => crate::t!("Custom").into_owned(),
+                _ => value.clone(),
+            },
+            value,
+        })
         .collect::<Vec<_>>();
-    let selected_theme = Some(ThemeChoice(ui_theme.name.clone()));
+    let selected_theme = theme_options
+        .iter()
+        .find(|choice| choice.value == ui_theme.name)
+        .cloned();
+
+    let language_options = crate::i18n::Language::ALL
+        .into_iter()
+        .map(|value| Labelled {
+            label: value.label(),
+            value,
+        })
+        .collect::<Vec<_>>();
+    let selected_language = language_options
+        .iter()
+        .find(|choice| choice.value == language)
+        .cloned();
 
     let palette = ui_theme.palette.to_iced();
     let colors = [
@@ -89,11 +109,11 @@ pub fn view_window<'a>(
         row![
             text(crate::tr!("options-language-label")).size(12).width(150),
             iced::widget::pick_list(
-                Some(language),
-                crate::i18n::Language::ALL,
-                |value| value.to_string(),
+                selected_language,
+                language_options,
+                |choice| choice.label.clone(),
             )
-            .on_select(Message::LanguageChanged)
+            .on_select(|choice| Message::LanguageChanged(choice.value))
             .width(sizing.width),
         ]
         .spacing(12)
@@ -125,9 +145,9 @@ pub fn view_window<'a>(
             iced::widget::pick_list(
                 selected_theme,
                 theme_options,
-                |value| value.to_string(),
+                |choice| choice.label.clone(),
             )
-            .on_select(|choice| Message::OptionsThemeChanged(choice.0))
+            .on_select(|choice| Message::OptionsThemeChanged(choice.value))
             .width(sizing.width),
         ]
         .spacing(12)
@@ -143,7 +163,9 @@ pub fn view_window<'a>(
     .width(sizing.width);
 
     let body = column![
-        scrollable(content).height(sizing.height),
+        // Keep the scrollbar in its own lane instead of floating over the
+        // controls at the trailing edge of the Options content.
+        scrollable(content).spacing(8).height(sizing.height),
         Space::new().height(12),
         row![Space::new().width(sizing.width), close],
     ]