fix(kwin): match the real capsule window class in the switcher rule

scripts/install-desktop-integration

@@ -27,7 +27,7 @@ Icon=pickgauge
 Terminal=false
 Categories=Utility;Monitor;
 Keywords=usage;quota;codex;claude;
-StartupWMClass=pickgauge
+StartupWMClass=Pickgauge
 EOF
 
 command -v update-desktop-database >/dev/null 2>&1 && update-desktop-database "$APPS_DIR" || true

scripts/install.sh

@@ -8,9 +8,9 @@ set -eu
 REPO="pickforge/pickgauge"
 APP_NAME="PickGauge"
 BIN_NAME="pickgauge"
-# The window's app_id (bundle identifier). The .desktop basename and
-# StartupWMClass must equal it or the running window shows a generic icon.
+# The window's app_id (bundle identifier) determines the .desktop basename.
 APP_ID="pickgauge"
+WM_CLASS="Pickgauge"
 
 # Environment overrides:
 #   PICKGAUGE_INSTALL_DIR  Linux AppImage target dir. Default: $HOME/.local/bin.
@@ -236,8 +236,8 @@ write_desktop_launcher() {
   launcher_command=$1
   launcher_icon=$2
   launcher_dir="${XDG_DATA_HOME:-$HOME/.local/share}/applications"
-  # Basename and StartupWMClass must equal the window's app_id so the desktop
-  # environment ties the running window to this entry (and its icon).
+  # The desktop environment uses the runtime window class to tie the running
+  # window to this entry (and its icon).
   launcher_file="$launcher_dir/$APP_ID.desktop"
 
   mkdir -p "$launcher_dir" 2>/dev/null || return 0
@@ -249,7 +249,7 @@ write_desktop_launcher() {
     printf 'Comment=Local AI usage tray\n'
     printf 'Exec="%s"\n' "$launcher_exec"
     printf 'Icon=%s\n' "$launcher_icon"
-    printf 'StartupWMClass=%s\n' "$APP_ID"
+    printf 'StartupWMClass=%s\n' "$WM_CLASS"
     printf 'Terminal=false\n'
     printf 'Categories=Development;\n'
     printf 'Keywords=pickgauge;usage;codex;claude;\n'

src-tauri/src/kwin.rs

@@ -20,7 +20,8 @@ use std::process::Command;
 
 const RULE_GROUP: &str = "pickgauge-float-keep-above";
 const FLOAT_TITLE: &str = "PickGauge Float";
-const WM_CLASS: &str = "pickgauge";
+// KWin wmclass matching is case-sensitive; GTK derives this runtime class from the binary name (hardware-verified on KDE Wayland).
+const WM_CLASS: &str = "Pickgauge";
 
 fn find_command(name: &str) -> Option<PathBuf> {
     let path = std::env::var_os("PATH")?;
@@ -33,7 +34,7 @@ fn find_command(name: &str) -> Option<PathBuf> {
     None
 }
 
-fn group_has_key(contents: &str, group: &str, key: &str) -> bool {
+fn group_value<'a>(contents: &'a str, group: &str, key: &str) -> Option<&'a str> {
     let header = format!("[{group}]");
     let mut in_group = false;
     for line in contents.lines() {
@@ -42,11 +43,25 @@ fn group_has_key(contents: &str, group: &str, key: &str) -> bool {
             in_group = trimmed == header;
             continue;
         }
-        if in_group && trimmed.starts_with(key) {
-            return true;
+        if in_group {
+            match trimmed.split_once('=') {
+                Some((candidate, value)) if candidate.trim() == key => {
+                    return Some(value.trim());
+                }
+                _ => {}
+            }
         }
     }
-    false
+    None
+}
+
+fn group_has_key(contents: &str, group: &str, key: &str) -> bool {
+    group_value(contents, group, key).is_some()
+}
+
+fn rule_is_current(contents: &str) -> bool {
+    group_has_key(contents, RULE_GROUP, "positionrule")
+        && group_value(contents, RULE_GROUP, "wmclass") == Some(WM_CLASS)
 }
 
 /// Whether the current session is a KDE Wayland compositor session — native
@@ -81,8 +96,7 @@ pub fn ensure_float_rule() {
     let rules_path = Path::new(&home).join(".config/kwinrulesrc");
     let existing_rules = std::fs::read_to_string(&rules_path).unwrap_or_default();
     let already_registered = existing_rules.contains(RULE_GROUP);
-    // "positionrule" inside our group marks the current revision; rewrite older ones.
-    if already_registered && group_has_key(&existing_rules, RULE_GROUP, "positionrule") {
+    if already_registered && rule_is_current(&existing_rules) {
         return;
     }
 
@@ -113,7 +127,7 @@ pub fn ensure_float_rule() {
     };
 
     write("Description", "PickGauge float capsule (managed by PickGauge)");
-    // Match: window class contains "pickgauge" AND title is exactly the
+    // Match: window class contains "Pickgauge" AND title is exactly the
     // float window title, so the main window is unaffected.
     write("wmclass", WM_CLASS);
     write("wmclassmatch", "2"); // substring
@@ -181,6 +195,11 @@ pub fn ensure_float_rule() {
 mod tests {
     use super::*;
 
+    #[test]
+    fn rule_uses_the_runtime_window_class() {
+        assert_eq!(WM_CLASS, "Pickgauge");
+    }
+
     #[test]
     fn native_wayland_kde_session_installs_the_rule() {
         // Also covers pickforge/pickgauge#49: the predicate takes no
@@ -234,12 +253,11 @@ mod tests {
     }
 
     #[test]
-    fn group_has_key_finds_a_key_in_the_current_revision() {
-        let contents = "[pickgauge-float-keep-above]\nskiptaskbar=true\npositionrule=3\n";
-        assert!(group_has_key(
-            contents,
-            "pickgauge-float-keep-above",
-            "positionrule"
-        ));
+    fn current_rule_requires_the_exact_runtime_window_class() {
+        let current = "[pickgauge-float-keep-above]\nwmclass=Pickgauge\npositionrule=3\n";
+        let stale = "[pickgauge-float-keep-above]\nwmclass=pickgauge\npositionrule=3\n";
+
+        assert!(rule_is_current(current));
+        assert!(!rule_is_current(stale));
     }
 }

tests/install-script-smoke.mjs

@@ -219,6 +219,7 @@ test("AppImage install writes a FUSE-aware wrapper, desktop entry, and icon", (r
   assert.match(readFileSync(command, "utf8"), new RegExp(appImage.replace(/[.*+?^${}()|[\]\\]/g, "\\$&")));
   assert.match(readFileSync(launcher, "utf8"), /Exec=".*\/\.local\/bin\/pickgauge"/);
   assert.match(readFileSync(launcher, "utf8"), /Icon=.*pickgauge/);
+  assert.match(readFileSync(launcher, "utf8"), /^StartupWMClass=Pickgauge$/m);
   assert.equal(existsSync(icon), true);
   assert.match(output, /Launch with `pickgauge`/);
   assertHeadlessForwarding(command, home);