Fall back to English instead of showing raw keys

Every namespace the fork added -- main_tabs, feed, cards, watch, browse,
search, player, and now account -- exists only in en.json, because the thirteen
translated language files predate them. get_text() consults the embedded
fallback dict and then gives up and returns the key, so a non-English UI read
"main_tabs.watch" on its own tabs. This round made that worse by adding more
English-only keys.

The fallback dict now carries those namespaces verbatim from en.json. It does
not translate anything -- a German UI shows English for these strings -- but
nothing shows a dotted key, and keys added later degrade the same way instead
of breaking. Translations that do exist still win: buttons.download is still
"Herunterladen" in German.

Verified across all fourteen language files: no key in the fork's namespaces
resolves to itself in any of them.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -88,6 +88,13 @@ records.
 
 ### Fixed
 
+- **A non-English interface no longer shows raw keys.** Every string SageTube
+  added — the tab names, the feed, cards, watch, browse, search, player and
+  account text — exists only in `en.json`, because the thirteen translated files
+  predate the fork. `get_text` returned the key itself, so the tabs literally
+  read `main_tabs.watch`. Those namespaces are now in the embedded English
+  fallback, so a missing translation reads as English rather than as a dotted
+  key. Translating the language files remains a separate job.
 - The error log filled with hundreds of `after creating texture: OpenGL error
   INVALID_ENUM` lines per session. They come from the GL driver, playback
   continues regardless, and they buried the errors that do matter, so they are

ytsage/utils/ytsage_localization.py

@@ -78,9 +78,139 @@ class LocalizationManager:
             "check_app_updates": "Check for SageTube updates on startup",
             "check_beta_updates": "Receive Beta Updates"
         },
-        # Only the keys added by SageTube live here; the rest of update_dialog
+        # --- SageTube's own strings -------------------------------------
-        # is in every language file already. Without this a non-English UI
+        # These namespaces exist only in en.json: the fork added them and the
-        # would show the raw key for the buttons below.
+        # thirteen translated files predate them. get_text() falls back to this
+        # dict before giving up and returning the key itself, so without these
+        # a non-English UI literally reads "main_tabs.watch" on its tabs.
+        # Keep in step with en.json when adding keys; translating the language
+        # files is the separate, larger job.
+        "main_tabs": {
+            "watch": "Watch",
+            "search": "Search",
+            "feed": "Feed",
+            "browse": "Browse",
+            "downloads": "Downloads"
+        },
+        "search": {
+            "placeholder": "Search YouTube...",
+            "button": "Search",
+            "searching": "Searching...",
+            "results_count": "{count} results",
+            "failed": "Search failed: {error}",
+            "button_tooltip": "Search YouTube"
+        },
+        "browse": {
+            "placeholder": "Paste a channel or playlist URL...",
+            "open": "Open",
+            "subscribe": "Subscribe",
+            "unsubscribe": "Unsubscribe",
+            "play_all": "Play all",
+            "download_playlist": "Download",
+            "tab_videos": "Videos",
+            "tab_shorts": "Shorts",
+            "tab_live": "Live",
+            "loading": "Loading...",
+            "entry_count": "{count} videos",
+            "failed": "Failed to load: {error}",
+            "hint": "Open a channel (youtube.com/@name) or playlist URL, or navigate here from Search.",
+            "open_tooltip": "Open this channel or playlist",
+            "subscribe_tooltip": "Follow this channel so its uploads appear in your Feed",
+            "unsubscribe_tooltip": "Stop following this channel",
+            "play_all_tooltip": "Queue everything loaded here",
+            "download_playlist_tooltip": "Open this playlist in Downloads",
+            "queued_loaded": "Queued {count} loaded videos — press Load more first to queue the rest"
+        },
+        "feed": {
+            "mode_local": "Local subscriptions",
+            "mode_account": "YouTube account (cookies)",
+            "refresh": "Refresh",
+            "subscriptions": "Subscriptions",
+            "no_subscriptions": "No subscriptions yet - subscribe from a channel page in Browse",
+            "refreshing": "Refreshing... {done}/{total}",
+            "refreshed": "{count} videos in feed",
+            "channel_failed": "A channel failed to refresh: {error}",
+            "fetching_account": "Fetching your subscription feed...",
+            "account_failed": "Account feed failed (are cookies valid?): {error}",
+            "subscribed": "Subscribed to {title}",
+            "unsubscribed": "Unsubscribed from {title}",
+            "open_channel": "Open channel",
+            "refresh_tooltip": "Fetch the latest uploads from every subscribed channel",
+            "mode_tooltip": "Where the feed comes from: your local subscriptions, or your signed-in YouTube account",
+            "refreshed_with_failures": "{count} videos — {failed} channel(s) could not be reached",
+            "account_needs_refresh": "Press Refresh to load your account feed",
+            "empty_no_subscriptions": "No subscriptions yet.\n\nFind channels in Search or Browse, then use Subscribe to follow them — their new uploads will appear here.",
+            "empty_not_refreshed": "Nothing here yet.\n\nPress Refresh to fetch the latest uploads from your subscriptions.",
+            "sign_in": "Sign in with cookies…",
+            "sign_in_tooltip": "Use your YouTube account via browser cookies, which enables the account feed",
+            "account_requires_cookies": "Requires signing in with cookies"
+        },
+        "cards": {
+            "play": "▶ Play",
+            "queue": "+ Queue",
+            "download": "⬇",
+            "load_more": "Load more",
+            "empty": "Nothing here yet",
+            "play_tooltip": "Play this video now",
+            "queue_tooltip": "Add to the play queue",
+            "download_tooltip": "Open in Downloads with this video ready to analyse",
+            "load_more_tooltip": "Load the next page of results"
+        },
+        "watch": {
+            "clear_queue": "Clear queue"
+        },
+        "player": {
+            "quality_auto": "Auto",
+            "subtitles": "CC",
+            "unavailable": "Video player unavailable",
+            "now_playing": "Now Playing",
+            "queue": "Queue",
+            "play": "Play",
+            "pause": "Pause",
+            "stream_stalled": "Stream failed to start after several attempts - YouTube may be throttling. Try again or pick a lower quality.",
+            "play_pause": "Play / pause  (Space)",
+            "fullscreen": "Fullscreen  (F)",
+            "seek_tooltip": "Seek through the video",
+            "quality_tooltip": "Maximum playback resolution",
+            "speed_tooltip": "Playback speed",
+            "volume_tooltip": "Volume",
+            "subtitles_tooltip": "Toggle subtitles  (C)",
+            "previous": "Previous in queue  (P)",
+            "next": "Next in queue  (N)",
+            "buffering": "Buffering…",
+            "act_play_pause": "Play / pause",
+            "act_seek_back_5": "Back 5 seconds",
+            "act_seek_fwd_5": "Forward 5 seconds",
+            "act_seek_back_10": "Back 10 seconds",
+            "act_seek_fwd_10": "Forward 10 seconds",
+            "act_seek_back_1": "Back 1 second",
+            "act_seek_fwd_1": "Forward 1 second",
+            "act_frame_back": "Previous frame",
+            "act_frame_fwd": "Next frame",
+            "act_vol_up": "Volume up",
+            "act_vol_down": "Volume down",
+            "act_mute": "Mute",
+            "act_unmute": "Unmute",
+            "act_speed_up": "Speed up",
+            "act_speed_down": "Slow down",
+            "act_speed_reset": "Normal speed",
+            "act_subtitles": "Subtitles on / off",
+            "act_fullscreen": "Fullscreen",
+            "act_leave_fullscreen": "Leave fullscreen",
+            "act_next": "Next in queue",
+            "act_previous": "Previous",
+            "act_start": "Back to start",
+            "act_end": "Jump to end",
+            "act_copy_url": "Copy video link",
+            "act_open_browser": "Open in browser"
+        },
+        "account": {
+            "signed_out": "Not signed in",
+            "signed_out_tooltip": "SageTube is not using a YouTube account. Sign in with browser cookies to use your subscription feed and reach age-restricted or members-only videos.",
+            "signed_in": "Account: {source}",
+            "signed_in_tooltip": "Using cookies from {source}. Click to change or clear them.",
+            "source_file": "cookie file"
+        },
         "update_dialog": {
             "skip_version": "Skip This Version",
             "skip_version_tooltip": "Never offer {version} again. Later versions will still be shown.",