style: translate all source code comments to English

German inline comments alongside English identifiers create a language
mismatch that makes the code harder to read for anyone not fluent in
German. All 28 affected comments across 14 files are now in English,
consistent with the rest of the project's written artifacts.

src/main/auth/authService.ts

@@ -1,4 +1,4 @@
-// Orchestriert den kompletten Twitch-Login-Lifecycle und hält den aktuellen Token-Status.
+// Orchestrates the full Twitch login lifecycle and tracks current token status.
 
 import { EventEmitter } from 'node:events'
 import {

src/main/auth/deviceCodeFlow.ts

@@ -92,7 +92,7 @@ export async function pollForToken(opts: PollOptions): Promise<PollOutcome> {
       return { kind: 'authorized', token }
     }
 
-    // Twitch liefert bei Pending einen 400 mit message-Feld.
+    // Twitch returns a 400 with a message field while the code is pending.
     let payload: ErrorResponse = {}
     try {
       const json = (await res.json()) as unknown

src/main/auth/tokenStore.ts

@@ -1,5 +1,5 @@
-// Verschlüsselte Persistenz für Twitch-Tokens.
-// Nutzt Electron safeStorage (OS-Keystore unter der Haube) — keine native Module nötig.
+// Encrypted persistence for Twitch tokens.
+// Uses Electron safeStorage (OS keystore under the hood) — no native modules required.
 
 import { app, safeStorage } from 'electron'
 import { promises as fs } from 'node:fs'
@@ -27,8 +27,8 @@ export async function saveTokens(tokens: StoredTokens): Promise<void> {
     const encrypted = safeStorage.encryptString(json)
     await fs.writeFile(path, encrypted)
   } else {
-    // Fallback: unverschlüsselt (z. B. headless Linux ohne Keyring).
-    // Datei nur für aktuellen User lesbar machen.
+    // Fallback: plaintext (e.g. headless Linux without a keyring).
+    // Restrict file permissions to the current user.
     await fs.writeFile(path, json, { mode: 0o600 })
   }
 }
@@ -48,7 +48,7 @@ export async function loadTokens(): Promise<StoredTokens | null> {
     try {
       json = safeStorage.decryptString(raw)
     } catch {
-      // Datei evtl. mit anderem Key geschrieben — als ungültig behandeln.
+      // File may have been written with a different key — treat as invalid.
       return null
     }
   } else {

src/main/index.ts

@@ -9,11 +9,12 @@ import { getHlsCacheEnabled } from './prefs/hlsCachePref'
 
 const isDev = !app.isPackaged
 
-// Erlaubt video.play() ohne vorangehende User-Geste (nötig, weil play() in hls.js-Callbacks
-// aufgerufen wird, die asynchron weit nach dem ursprünglichen Click-Event stattfinden).
+// Allows video.play() without a prior user gesture — play() is called from hls.js callbacks
+// that fire asynchronously long after the original click event.
 app.commandLine.appendSwitch('autoplay-policy', 'no-user-gesture-required')
-// Explizite Cache-Größe verhindert Chromiums dynamische Größenberechnung, die bei
-// wechselndem freiem Speicherplatz zu "Invalid cache (current) size"-Fehlern führt.
+// Explicit cache size prevents Chromium's dynamic sizing, which causes "Invalid cache (current)
+// size" errors when available disk space fluctuates.
+
 app.commandLine.appendSwitch('disk-cache-size', String(500 * 1024 * 1024))
 
 function createWindow(): BrowserWindow {

src/main/input/gamepadReader.ts

@@ -41,7 +41,7 @@ const INPUT_EVENT_SIZE = 24
 const EV_KEY = 0x01
 const EV_ABS = 0x03
 
-// Button-Codes (BTN_GAMEPAD-Bereich) – konsistent über alle Controller und Treiber
+// Button codes (BTN_GAMEPAD range) — consistent across all controllers and drivers
 const BTN_SOUTH = 0x130
 const BTN_EAST  = 0x131
 const BTN_NORTH = 0x133
@@ -70,10 +70,10 @@ const BUTTON_MAP: Record<number, string> = {
   [BTN_TR2]:   'r2',
 }
 
-const STICK_THRESHOLD = 16384  // ~50% von 32767
+const STICK_THRESHOLD = 16384  // ~50% of 32767
 const REPEAT_INITIAL_MS = 400
 const REPEAT_INTERVAL_MS = 150
-// Trigger-Achsen sollen kein Auto-Repeat auslösen (300s-Sprünge nicht wiederholen)
+// Trigger axes must not fire auto-repeat (avoid repeating 300 s jumps)
 const NO_REPEAT_ABS_CODES = new Set([ABS_Z, ABS_RZ])
 
 interface AxisState {
@@ -96,7 +96,7 @@ function findEventDevice(jsDevicePath: string): string | null {
     const eventEntry = entries.find((e) => /^event\d+$/.test(e))
     if (eventEntry) return `/dev/input/${eventEntry}`
   } catch {
-    // Kein /sys-Zugriff oder Device verschwunden
+    // No /sys access or device has disappeared
   }
   return null
 }
@@ -400,7 +400,7 @@ export function startGamepadReader(getWindow: () => BrowserWindow | null): () =>
             console.log(`[gamepad] geöffnet (evdev): ${jsPath} → ${eventPath}`)
           }
         } else {
-          // Fallback auf altes Joystick-API wenn kein /sys-Mapping gefunden
+          // Fallback to legacy joystick API when no /sys mapping is found
           reader = new JoystickFallbackReader(jsPath, onKey)
           if (reader.start()) {
             readers.set(jsPath, reader)
@@ -417,7 +417,7 @@ export function startGamepadReader(getWindow: () => BrowserWindow | null): () =>
         }
       }
     } catch {
-      // /dev/input nicht zugänglich
+      // /dev/input not accessible
     }
   }
 

src/main/ipc/handlers.ts

@@ -85,7 +85,7 @@ export function registerIpcHandlers(
   )
   ipcMain.handle(IPC.playbackStop, () => playback.stop())
   ipcMain.handle(IPC.playbackPause, () => {
-    // Fokus auf Electron-Fenster zurückholen (Windows: Win Gamepad API braucht Fokus)
+    // Bring Electron window back into focus (Windows: Gamepad API requires window focus)
     for (const win of BrowserWindow.getAllWindows()) win.focus()
   })
   ipcMain.handle(

src/main/playback/streamlink.ts

@@ -68,7 +68,7 @@ export function getStreamUrl(url: string, quality: string): Promise<string> {
     proc.stdout?.on('data', (d: Buffer) => { out += d.toString() })
     proc.on('error', reject)
     proc.on('exit', (code) => {
-      // Nimm die letzte Zeile die mit https:// beginnt — ignoriert Info-/Warn-Zeilen
+      // Take the last line starting with https:// — skips info/warn lines from streamlink
       const hlsUrl = out.split('\n').map((l) => l.trim()).filter((l) => l.startsWith('https://')).at(-1) ?? ''
       if (code === 0 && hlsUrl) {
         resolve(hlsUrl)

src/main/twitch/helixClient.ts

@@ -308,7 +308,7 @@ export class HelixClient {
       }
     })
 
-    // Live-Kanäle zuerst, dann alphabetisch
+    // Live channels first, then alphabetical
     return channels.sort((a, b) => {
       if (a.isLive !== b.isLive) return a.isLive ? -1 : 1
       return a.broadcasterName.localeCompare(b.broadcasterName)

src/renderer/src/components/VideoPlayer.tsx

@@ -70,12 +70,12 @@ export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
       }
     }))
 
-    // HLS-Player initialisieren und URL laden
+    // Initialize hls.js and load the URL
     useEffect(() => {
       const video = videoRef.current
       if (!video) return
 
-      // Bestehende hls.js-Instanz zerstören
+      // Tear down any existing hls.js instance
       if (hlsRef.current) {
         hlsRef.current.destroy()
         hlsRef.current = null
@@ -87,7 +87,7 @@ export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
         const hls = new Hls({ enableWorker: false })
         hlsRef.current = hls
 
-        // Erst Media attachieren, dann Source laden (zuverlässiger in Electron/Chromium)
+        // Attach media first, then load the source — more reliable in Electron/Chromium
         hls.attachMedia(video)
         console.log('[VideoPlayer] attachMedia aufgerufen')
 
@@ -101,9 +101,8 @@ export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
           if (startPosition > 0 && !isLive) {
             video.currentTime = startPosition
           }
-          // Mit der korrekten Reihenfolge (attachMedia → MEDIA_ATTACHED → loadSource)
-          // ist die MediaSource beim MANIFEST_PARSED-Event bereits am Video-Element —
-          // play() kann direkt aufgerufen werden.
+          // With the correct order (attachMedia → MEDIA_ATTACHED → loadSource)
+          // the MediaSource is already attached at MANIFEST_PARSED — play() is safe to call.
           video.play().then(() => {
             console.log('[VideoPlayer] play() erfolgreich')
           }).catch((err: unknown) => {
@@ -119,7 +118,7 @@ export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
           }
         })
       } else if (video.canPlayType('application/vnd.apple.mpegurl')) {
-        // Native HLS (nicht Electron, aber als Fallback)
+        // Native HLS (not Electron, but as a fallback)
         video.src = hlsUrl
         if (startPosition > 0 && !isLive) {
           video.currentTime = startPosition
@@ -138,7 +137,7 @@ export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
     // eslint-disable-next-line react-hooks/exhaustive-deps
     }, [hlsUrl])
 
-    // VOD-Fortschritt alle 5s an Main-Prozess melden (für SQLite History)
+    // Report VOD progress every 5 s to the main process (SQLite history)
     useEffect(() => {
       if (!vodId || !durationSeconds || isLive) return
       const id = setInterval(() => {

src/renderer/src/context/SettingsContext.tsx

@@ -50,7 +50,7 @@ function saveSettings(s: AppSettings): void {
   try {
     localStorage.setItem(STORAGE_KEY, JSON.stringify(s))
   } catch {
-    // localStorage nicht verfügbar — ignorieren
+    // localStorage not available — ignore
   }
 }
 

src/renderer/src/screens/AppShell.tsx

@@ -29,11 +29,11 @@ export default function AppShell({ onLogout }: Props): JSX.Element {
   const [quitDialogOpen, setQuitDialogOpen] = useState(false)
   const [quitDialogChoice, setQuitDialogChoice] = useState<QuitChoice>('no')
 
-  // Kanal-Info für den globalen Overlay — AppShell-spezifisch, kein Playback-State
+  // Channel info for the global overlay — AppShell-specific, not part of playback state
   const [liveChannel, setLiveChannel] = useState<FollowedChannelInfo | null>(null)
   const [livePosition, setLivePosition] = useState(0)
 
-  // Globale Playback-Session — aktiv wenn kein ChannelScreen offen ist
+  // Global playback session — active when no ChannelScreen is open
   const globalSession = usePlaybackSession({
     active: !selectedChannel,
     onStopped: () => { setLiveChannel(null); setLivePosition(0) },
@@ -84,7 +84,7 @@ export default function AppShell({ onLogout }: Props): JSX.Element {
     setSelectedChannel(ch)
   }, [])
 
-  // Direkt-Start: kein ChannelScreen — globaler Overlay startet sofort
+  // Direct start: no ChannelScreen — global overlay starts immediately
   const handleStartLive = useCallback((ch: FollowedChannelInfo) => {
     setLiveChannel(ch)
     void startGlobalLive(ch.broadcasterLogin)
@@ -108,11 +108,11 @@ export default function AppShell({ onLogout }: Props): JSX.Element {
     setSelectedCategory(game)
   }, [])
 
-  // Key-Handler für den globalen Playback-Overlay (B=Stop, A=Pause, Pfeile=Seek)
+  // Key handler for the global playback overlay (B=Stop, A=Pause, arrows=Seek)
   useEffect(() => {
     if (!isGlobalPlaying) return
     const onKey = (e: KeyboardEvent): void => {
-      // Quality-Panel hat Vorrang wenn geöffnet
+      // Quality panel takes priority when open
       if (liveQualityPanelOpen) {
         if (e.key === 'ArrowUp') {
           e.preventDefault()
@@ -177,7 +177,7 @@ export default function AppShell({ onLogout }: Props): JSX.Element {
     return () => window.removeEventListener('keydown', onKey)
   }, [isGlobalPlaying, livePlayState, handleStopLive, liveQualityPanelOpen, liveAvailableQualities, liveQualityFocusedIndex, liveCurrentQuality, liveChannel, handleLiveQualityChange])
 
-  // Key-Handler für die Sidebar (wenn sie den Fokus hat)
+  // Key handler for the sidebar (when it has focus)
   useEffect(() => {
     if (region !== 'sidebar') return
     const onKey = (e: KeyboardEvent): void => {

src/renderer/src/screens/BrowseScreen.tsx

@@ -73,7 +73,7 @@ export default function BrowseScreen({
     void load()
   }, [load])
 
-  // Nächste Seite automatisch nachladen wenn letztes Element fokussiert wird
+  // Auto-load next page when the last item gets focus
   useEffect(() => {
     if (focusRegion !== 'grid' || loadState !== 'ok') return
     if (gridIndex === topGames.length - 1 && nextCursor && !isLoadingMore) {
@@ -179,7 +179,7 @@ export default function BrowseScreen({
     return () => window.removeEventListener('keydown', onKey)
   }, [hasFocus, loadState, focusRegion, shelfIndex, gridIndex, topStreams, topGames, getGridColumns, onRequestSidebar, onSelectChannel, onStartLive, onSelectCategory, load])
 
-  // Grid-Karte in den Viewport scrollen wenn fokussiert
+  // Scroll the focused grid card into the viewport
   useEffect(() => {
     if (focusRegion !== 'grid') return
     const grid = gridRef.current

src/renderer/src/screens/ChannelScreen.tsx

@@ -62,7 +62,7 @@ export default function ChannelScreen({ channel, onBack }: Props): JSX.Element {
       .finally(() => setChaptersLoading(false))
   }
 
-  // Playback-Session — ChannelScreen ist immer der aktive Eigentümer wenn gemountet
+  // Playback session — ChannelScreen is always the active owner while mounted
   const session = usePlaybackSession({
     active: true,
     onStarted: (ev) => {
@@ -134,7 +134,7 @@ export default function ChannelScreen({ channel, onBack }: Props): JSX.Element {
     const onKey = (e: KeyboardEvent): void => {
       const isPlaying = playState === 'playing' || playState === 'starting' || playState === 'paused'
 
-      // Kapitel-Panel hat oberste Priorität (gilt auch während Wiedergabe)
+      // Chapter panel has top priority (also applies during playback)
       if (focusRegion === 'chapters' && chapterPanelVod) {
         const duringPlayback = isPlaying
         if (e.key === 'Escape') {
@@ -175,9 +175,9 @@ export default function ChannelScreen({ channel, onBack }: Props): JSX.Element {
         return
       }
 
-      // Während der Wiedergabe: nur Playback-Steuerung erlauben, keine Navigation
+      // During playback: allow only playback controls, block screen navigation
       if (isPlaying) {
-        // Quality-Panel hat Vorrang wenn geöffnet
+        // Quality panel takes priority when open
         if (qualityPanelOpen) {
           if (e.key === 'ArrowUp') {
             e.preventDefault()

src/renderer/src/screens/FollowingScreen.tsx

@@ -50,13 +50,13 @@ export default function FollowingScreen({
     if (!hasFocus) return
 
     const onKey = (e: KeyboardEvent): void => {
-      // Refresh über [Y] funktioniert immer
+      // [Y] refresh always works regardless of focus region
       if (e.key === 'y' || e.key === 'Y') {
         void load()
         return
       }
 
-      // Bei leeren / Fehler-Zuständen nur Left zum Sidebar zulassen
+      // In empty / error states only allow Left to reach the sidebar
       if (loadState !== 'ok' || channels.length === 0) {
         if (e.key === 'ArrowLeft') {
           e.preventDefault()

src/renderer/src/screens/LoginScreen.tsx

@@ -17,7 +17,7 @@ export default function LoginScreen({ onAuthorized }: Props): JSX.Element {
   const [phase, setPhase] = useState<Phase>({ kind: 'idle' })
   const startBtnRef = useRef<HTMLButtonElement>(null)
 
-  // Initial: prüfen ob Client-ID konfiguriert ist.
+  // On mount: check whether the client ID is configured.
   useEffect(() => {
     void window.t4sd.auth.isConfigured().then((ok) => {
       if (!ok) setPhase({ kind: 'not-configured' })
@@ -35,7 +35,7 @@ export default function LoginScreen({ onAuthorized }: Props): JSX.Element {
     return () => window.removeEventListener('keydown', onKey)
   }, [phase])
 
-  // Auth-Events aus Main abonnieren.
+  // Subscribe to auth events from the main process.
   useEffect(() => {
     const off = window.t4sd.auth.onEvent((event) => {
       switch (event.kind) {
@@ -59,7 +59,7 @@ export default function LoginScreen({ onAuthorized }: Props): JSX.Element {
     return off
   }, [onAuthorized])
 
-  // Countdown für die aktive Phase.
+  // Countdown tick for the awaiting phase.
   useEffect(() => {
     if (phase.kind !== 'awaiting') return
     if (phase.remainingSec <= 0) return