Troubleshooting

Common issues and how to resolve them. Most problems fall into one of a few buckets - the overlay shows but subtitles don't (see MPV Connection), cards aren't being created or come out empty (see AnkiConnect), or word lookups don't appear (see Yomitan). If an error message popped up on screen, search this page for the exact text - most headings below are quoted error strings.

MPV Connection

Overlay starts but shows no subtitles

SubMiner connects to mpv via a Unix socket (or named pipe on Windows). If the socket does not exist or the path does not match, the overlay will appear but subtitles will never arrive.

Ensure mpv is running with --input-ipc-server=/tmp/subminer-socket.
If you use a custom socket path, set it in both your mpv config and SubMiner config (mpv.socketPath).
The subminer wrapper script sets the socket automatically when it launches mpv. If you launch mpv yourself, the --input-ipc-server flag is required.

SubMiner retries the connection automatically with increasing delays (200 ms, 500 ms, 1 s, 2 s on first connect; 1 s, 2 s, 5 s, 10 s on reconnect). If mpv exits and restarts, the overlay reconnects without needing a restart.

If the overlay never appears at all, see Playback Startup Flow for how a managed launch starts mpv and brings up the overlay.

Logging and App Mode

Default log output is warn.
Use --log-level for more/less output.
Use --dev/--debug only to force app/dev mode (for example to get dev behavior from the overlay/app); they do not change log verbosity.
You can combine both, for example SubMiner.AppImage --start --dev --log-level debug, when you need maximum diagnostics.

Performance and Resource Impact

At a glance

Baseline: SubMiner --start is usually lightweight for normal playback.
Common spikes come from:
- first subtitle parse/tokenization bursts
- media generation (ffmpeg audio/image and AVIF paths)
- media sync and subtitle tooling (alass, ffsubsync)
- ankiConnect enrichment (plus polling overhead when proxy mode is disabled)

If playback feels sluggish

Reduce overlay workload:

set secondary subtitles hidden:
- secondarySub.defaultMode: "hidden"
disable optional enrichment:
- subtitleStyle.enableJlpt: false
- subtitleStyle.frequencyDictionary.enabled: false

Reduce rendering pressure:

lower subtitleStyle.css["font-size"]
keep overlay complexity minimal during heavy CPU periods

Reduce media overhead:

keep ankiConnect.media.imageType set to static (avoid animated AVIF unless needed)
lower ankiConnect.media.imageQuality
reduce ankiConnect.media.maxMediaDuration

Lower integration cost:

disable AI translation when not needed (ankiConnect.ai.enabled: false)
if needed, run immersion telemetry with lower duration expectations (immersionTracking.enabled: false for constrained sessions)
favor the default lightweight YouTube subtitle startup settings on low-resource systems

Practical low-impact profile

json

{
  "subtitleStyle": {
    "css": {
      "font-size": "30px"
    },
    "enableJlpt": false,
    "frequencyDictionary": {
      "enabled": false
    }
  },
  "secondarySub": {
    "defaultMode": "hidden"
  },
  "ankiConnect": {
    "media": {
      "imageType": "static",
      "imageQuality": 80,
      "maxMediaDuration": 12
    },
    "ai": {
      "enabled": false
    }
  },
  "immersionTracking": {
    "enabled": false
  }
}

If usage is still high

Confirm only one SubMiner instance is running.
Check whether bottlenecks are ffmpeg, yt-dlp, or sync tooling in system monitor.
Keep the default warn level for normal use; raise to info or debug only for targeted diagnosis.
Reproduce once with SubMiner.AppImage --start --log-level debug and open DevTools (y then d) if freezes recur.

"Failed to parse MPV message"

Logged when a malformed JSON line arrives from the mpv socket. Usually harmless - SubMiner skips the bad line and continues. If it happens constantly, check that nothing else is writing to the same socket path.

Updates

"Update check failed"

Manual update checks show this when GitHub Releases or updater metadata cannot be reached. Check your network connection, then try again from the tray menu or:

bash

subminer -u

Automatic checks log failures quietly so playback is not interrupted.

"SubMiner is up to date" but a prerelease exists

SubMiner uses the configured release channel for update checks. Set updates.channel to "prerelease" in config.jsonc when you want update checks to include beta and RC releases.

Launcher update shows a sudo command

The detected launcher is installed in a protected path such as /usr/local/bin/subminer or /usr/bin/subminer. SubMiner does not elevate itself. Run the command shown in the popup to replace the launcher after checksum verification.

OSD update notification did not appear

updates.notificationType: "osd" uses the legacy mpv OSD path. If mpv is disconnected, SubMiner logs the update and does not force-start the overlay. Use "system" for OS notifications, "both" for overlay + OS notifications, or "osd-system" in config.jsonc if you want the legacy OSD + OS combination.

AnkiConnect

"AnkiConnect: unable to connect"

First confirm you've completed the Anki Integration prerequisites - Anki must be running with the AnkiConnect add-on installed.

SubMiner connects to the active Anki endpoint:

ankiConnect.url (direct mode, default http://127.0.0.1:8765)
http://<ankiConnect.proxy.host>:<ankiConnect.proxy.port> (proxy mode)

This error means the active endpoint is unavailable, or (in proxy mode) the proxy cannot reach ankiConnect.proxy.upstreamUrl.

If you changed the AnkiConnect port, update ankiConnect.url (or ankiConnect.proxy.upstreamUrl if using proxy mode).
If using external Yomitan/browser clients, confirm they point to your SubMiner proxy URL.

SubMiner retries with exponential backoff (up to 5 s) and suppresses repeated error logs after 5 consecutive failures. When Anki comes back, you will see "AnkiConnect connection restored".

Cards are created but fields are empty

Field names in your config must match your Anki note type exactly (case-sensitive). Check ankiConnect.fields - for example, if your note type uses SentenceAudio but your config says Audio, the field will not be populated.

See Anki Integration for the full field mapping reference.

"Update failed" OSD message

Shown when SubMiner tries to update a card that no longer exists, or when AnkiConnect rejects the update. Common causes:

The card was deleted in Anki between creation and enrichment update.
The note type changed and a mapped field no longer exists.

Overlay

Overlay does not appear

Confirm SubMiner is running: SubMiner.AppImage --start or check for the process.
On Linux, the overlay requires a supported window backend. Hyprland and Sway have native Wayland support; all other compositors require both mpv and SubMiner to run under X11 or Xwayland (xdotool and xwininfo must be installed).
On macOS, grant Accessibility permission to SubMiner in System Settings > Privacy & Security > Accessibility.

Overlay appears but clicks pass through / cannot interact

Make sure you are hovering over subtitle text - the overlay only becomes interactive when the cursor is over a subtitle.
On macOS/Windows: toggle the overlay off and back on (Alt+Shift+O) to re-enable pointer events.
On Linux: mouse event handling is unreliable in some Electron/compositor combinations. If clicks consistently fail, toggle the overlay off, click the underlying mpv window, then toggle it back on.

Overlay briefly freezes after a modal/runtime error

Renderer errors now trigger an automatic recovery path. You should see a short toast ("Renderer error recovered. Overlay is still running.").
Recovery closes any open modal and restores click-through/shortcuts automatically without interrupting mpv playback.
If errors keep recurring, toggle the overlay's DevTools using overlay chord y then d (or global F12) and inspect the renderer overlay recovery error payload for stack trace + modal/subtitle context.

Overlay is on the wrong monitor or position

SubMiner positions the overlay by tracking the mpv window. If tracking fails:

Hyprland: Ensure hyprctl is available.
Sway: Ensure swaymsg is available.
X11: Ensure xdotool and xwininfo are installed.

If the overlay position is slightly off, right-click and drag on subtitle text to fine-tune the overlay subtitle offset.

Yomitan

If you haven't set up dictionaries yet, see Yomitan setup first.

"Yomitan extension not found in any search path"

SubMiner bundles Yomitan and searches for it in these locations (in order):

build/yomitan (local/source build output)
<resources>/yomitan (Electron resources path)
/usr/share/SubMiner/yomitan
~/.config/SubMiner/yomitan (user-data fallback on Linux)

SubMiner does not load the source tree directly from vendor/subminer-yomitan; source builds must produce build/yomitan first.

If you installed from the AppImage and see this error, the package may be incomplete. Re-download the AppImage or place the unpacked Yomitan extension manually in ~/.config/SubMiner/yomitan.

Yomitan lookup popup does not appear when hovering words or triggering lookup

Verify Yomitan loaded successfully - check the terminal output for "Loaded Yomitan extension".
Yomitan requires dictionaries to be installed. Open Yomitan settings (Alt+Shift+Y or SubMiner.AppImage --yomitan) and confirm at least one dictionary is imported.
If yomitan.externalProfilePath is set, import/check dictionaries in the external app/profile instead. SubMiner treats that profile as read-only and does not open its own Yomitan settings window.
If the overlay shows subtitles but hover lookup never resolves on tokens, the tokenizer may have failed. See the MeCab section below.

MeCab / Tokenization

"MeCab not found on system"

This is informational, not an error. SubMiner tokenization is driven by Yomitan's internal parser. MeCab availability checks may still run for auxiliary token metadata, but MeCab is not used as a tokenization fallback path.

To install MeCab:

Arch Linux: sudo pacman -S mecab mecab-ipadic
Ubuntu/Debian: sudo apt install mecab libmecab-dev mecab-ipadic-utf8
macOS: brew install mecab mecab-ipadic

Words are not segmented correctly

Japanese word boundaries depend on Yomitan parser output. If segmentation seems wrong:

Verify Yomitan dictionaries are installed and active.
Note that CJK characters without spaces are segmented using parser heuristics, which is not always perfect.

Character Dictionary

Character names from AniList are matched and highlighted in subtitles via the bundled Yomitan. See Character Dictionary for setup and the full troubleshooting list - the most common issues:

Names not highlighting: Confirm subtitleStyle.nameMatchEnabled is true, and that the current media resolved to an AniList entry (SubMiner needs a media ID to fetch characters). No AniList account or token is required - character data uses public GraphQL queries.
Inline portraits missing: Confirm subtitleStyle.nameMatchImagesEnabled is true. Portraits also require AniList to return an image and the download to succeed during snapshot generation.
Wrong characters showing: Open the in-app manager (Ctrl/Cmd+D) and use Override to pin the correct AniList match for the series.
Feature unavailable: If yomitan.externalProfilePath is set, SubMiner runs in read-only external-profile mode and its character-dictionary features are disabled.

Media Generation

"FFmpeg not found"

SubMiner uses FFmpeg to extract audio clips and generate screenshots. Install it:

Arch Linux: sudo pacman -S ffmpeg
Ubuntu/Debian: sudo apt install ffmpeg
macOS: brew install ffmpeg

Without FFmpeg, card creation still works but audio and image fields will be empty.

Audio or screenshot generation hangs

Media generation has a 30-second timeout (60 seconds for animated AVIF). If your video file is on a slow network mount or the codec requires software decoding, generation may time out. Try:

Using a local copy of the video file.
Reducing media.imageQuality or switching from avif to static image type.
Checking that media.maxMediaDuration is not set too high.

Shortcuts

"Failed to register global shortcut"

Global shortcuts (Alt+Shift+O, Alt+Shift+Y) may conflict with other applications or desktop environment keybindings.

Check your DE/WM keybinding settings for conflicts.
Change the shortcut in your config under shortcuts.toggleVisibleOverlayGlobal.
On Wayland, global shortcut registration has limitations depending on the compositor. Only Hyprland and Sway are supported natively - see the Hyprland section below for shortcut passthrough rules. Other Wayland compositors require X11/Xwayland.

Overlay keybindings not working

Overlay-local shortcuts (Space, arrow keys, etc.) only work when the overlay window has focus. Click on the overlay or use the global shortcut to toggle it to give it focus.

Subtitle Timing

"Subtitle timing not found; copy again while playing"

This OSD message appears when you try to mine a sentence but SubMiner has no timing data for the current subtitle. Causes:

The video is paused and no subtitle has been received yet.
The subtitle track changed and timing data was cleared.
You are using an external subtitle file that mpv has not fully loaded.

Resume playback and wait for the next subtitle to appear, then try mining again.

Subtitle Sync (Subsync)

Both alass and ffsubsync are optional external dependencies. Subtitle syncing requires at least one of them to be installed.

"Configured alass executable not found"

Install alass or configure the path:

Arch Linux (AUR): paru -S alass
Cargo: cargo install alass-cli
Set the path: subsync.alass_path in your config.

"Configured ffsubsync executable not found"

Install ffsubsync or configure the path:

Arch Linux (AUR): paru -S python-ffsubsync
pip: pip install ffsubsync
Must be on PATH or configured via subsync.ffsubsync_path in your config.

"Subtitle synchronization failed"

If subtitle sync fails:

Ensure the reference subtitle track exists in the video (alass requires a source track).
Check that ffmpeg is available (used to extract the internal subtitle track).
Try running the sync tool manually to see detailed error output.
ffsubsync requires local files and cannot handle remote media streams (e.g., streaming URLs).

Jimaku

"Jimaku request failed" or HTTP 429

The Jimaku API has rate limits. If you see 429 errors, wait for the retry duration shown in the OSD message and try again. If you have a Jimaku API key, set it in jimaku.apiKey or jimaku.apiKeyCommand to get higher rate limits.

Platform-Specific

Linux

Wayland (Hyprland/Sway only): Native Wayland support is limited to Hyprland and Sway. Window tracking uses compositor-specific commands (hyprctl / swaymsg). If these are not on PATH, tracking will fail silently. Other Wayland compositors (KDE Plasma, GNOME, …) are not supported natively - both mpv and SubMiner must run under X11 or Xwayland instead. On those sessions SubMiner forces XWayland automatically for itself and for every mpv it launches (see KDE Plasma & other Wayland compositors).
X11 / Xwayland: Requires xdotool, xprop, and xwininfo. If missing, the overlay cannot track the mpv window position. This is the required backend for any Wayland compositor other than Hyprland or Sway - both mpv and SubMiner must be running under X11/Xwayland for window tracking and for the overlay to stay above mpv (Wayland forbids clients from controlling window stacking). SubMiner uses a managed X11 overlay while mpv is windowed, switches to an override-redirect X11 overlay while tracked mpv is fullscreen, and hides/releases that overlay when another X11/Xwayland app takes focus. The visible overlay stays hidden until SubMiner has tracked mpv geometry, so startup should not create a display-sized fallback overlay while tokenization warms up.
Tray icon missing: SubMiner creates an Electron tray icon in --background mode, but Linux trays require a StatusNotifier/AppIndicator host. Hyprland does not provide one by itself; enable a tray in Waybar, Hyprpanel, or another panel. If Electron cannot register the tray, SubMiner logs a warning that mentions the missing tray host.
Mouse passthrough: On Linux X11/Xwayland, SubMiner uses xdotool to poll the cursor and only enables overlay input while the cursor is over subtitle or popup regions. Outside those regions, pointer input passes through to mpv. Native Wayland compositors other than Hyprland/Sway cannot provide the stacking control SubMiner needs.

Hyprland

SubMiner's overlay is a transparent, frameless Electron window that must be kept above mpv. SubMiner tries to apply the floating, borderless, no-shadow, and no-blur properties itself each time it places the overlay. It detects Hyprland's active config provider and uses Lua hl.dsp.window.* dispatchers for recent Hyprland Lua configs, or the legacy dispatcher syntax for older hyprlang configs. On many configurations that is enough, but if your Hyprland version doesn't honor those runtime dispatches - or a broad rule in your config forces opacity/blur on every window - add explicit window rules so the overlay is exempt. You also need pass bindings to forward global shortcuts to SubMiner (see below).

Overlay is not transparent or has a visible border

Add a window rule matching SubMiner's window class. Recent Hyprland uses the Lua config format:

lua

hl.window_rule({
  match = { class = "^SubMiner$" },
  float = true,
  border_size = 0,
  xray = false,
  no_shadow = true,
  no_blur = true,
  no_dim = true,
  opaque = true,
  dim_around = false,
  opacity = "1.0 override 1.0 override",
})

On older Hyprland releases that still use the hyprlang config (hyprland.conf), use the equivalent windowrule lines:

ini

windowrule = float on, match:class SubMiner
windowrule = border_size 0, match:class SubMiner
windowrule = xray off override, match:class SubMiner
windowrule = no_shadow on, match:class SubMiner
windowrule = no_blur on, match:class SubMiner

If you still see a solid background or visual artifacts instead of the mpv video underneath, the culprit is almost always a global opacity/blur rule applying to the overlay - the opaque/opacity and no_blur fields above override it.

Global shortcuts not working

On Hyprland, Electron cannot register global shortcuts on its own. You must explicitly pass keybindings to SubMiner using pass rules:

ini

bind = ALT SHIFT, O, pass, class:^(SubMiner)$
bind = ALT SHIFT, Y, pass, class:^(SubMiner)$

Add a pass rule for each global shortcut you configure. The defaults are Alt+Shift+O (toggle overlay) and Alt+Shift+Y (Yomitan settings). If you remap shortcuts.toggleVisibleOverlayGlobal to a different key, update the pass rule to match.

Without these rules, Hyprland intercepts the keypresses before they reach SubMiner, and the shortcuts silently do nothing.

Overlay stays behind mpv after fullscreen

SubMiner watches mpv's fullscreen property and refreshes the overlay geometry when it changes. If the overlay still does not move or rise above fullscreen mpv, confirm that the mpv IPC socket is connected and that hyprctl -j clients and hyprctl -j monitors work from the same environment that launched SubMiner.

For more details, see the Hyprland docs on global keybinds and window rules.

KDE Plasma & other Wayland compositors

On any Wayland session that is not Hyprland or Sway (KDE Plasma, GNOME, and others), the overlay can only stay above mpv when both processes run under XWayland - the Wayland protocol forbids clients from controlling window stacking, so the overlay's "always on top" becomes a no-op on a native Wayland surface.

SubMiner handles this automatically:

It launches its own window under XWayland (it sets --ozone-platform-hint=x11).
Every mpv it launches (via the subminer launcher, Jellyfin, or YouTube) is pinned to XWayland too - Wayland environment hints are stripped and an X11 GPU context (--gpu-context=x11egl,x11) is applied.
While mpv is windowed, the overlay is a managed X11 window owned by the tracked mpv window (WM_TRANSIENT_FOR), so it stays above mpv while other foreground X11/Xwayland apps can still cover both windows.
While tracked mpv is fullscreen, SubMiner swaps the visible overlay to a focusable-false X11 override-redirect window. That path can stay above the active fullscreen mpv window without requiring a KDE/KWin-specific rule, and SubMiner hides/releases it when mpv is no longer the active X11/Xwayland window.
The visible overlay is shown inactive on Linux, so normal hover should not steal keyboard focus from mpv.
During startup and fullscreen transitions, SubMiner waits for tracked mpv geometry before showing the visible overlay and skips the fullscreen restack hide/show path after mpv leaves fullscreen. That avoids a temporary full-screen overlay or black window while the subtitle tokenizer and Yomitan warmups finish.
If the subtitle sidebar is open during a windowed/fullscreen transition, SubMiner restores it on the replacement overlay window. Subtitle hit regions are also refreshed as soon as the first measured subtitle line is reported, so hover and Yomitan lookup should work on the first visible line.

Requirements: xdotool, xprop, and xwininfo must be installed. SubMiner uses root _NET_ACTIVE_WINDOW from xprop for focus detection and falls back to xdotool getactivewindow when that signal is unavailable.

Overlay sits behind mpv / pause-on-hover and Yomitan stop working

This almost always means mpv came up as a native Wayland window that the XWayland overlay cannot cover. It happens when mpv is launched manually (your own command), because SubMiner can only force XWayland on the mpv processes it launches itself. Fix it one of these ways:

Launch playback through SubMiner (the subminer launcher or the tray), which forces XWayland for you, or
Force XWayland in your own mpv invocation, e.g. mpv --gpu-context=x11egl …, or launch with WAYLAND_DISPLAY= mpv …, or set gpu-context=x11egl in your mpv.conf.

To confirm mpv is on XWayland, xdotool search --class mpv should return a window id (a native Wayland mpv returns nothing).

Overlay stays above an unrelated foreground app

SubMiner can only detect focus for X11/Xwayland windows in this mode. If a native Wayland app covers mpv but the overlay stays visible, run that app under Xwayland too or use Hyprland/Sway native support. Generic X11 cannot observe native Wayland foreground windows.

macOS

Accessibility permission: Required for window tracking. Grant it in System Settings > Privacy & Security > Accessibility.
Gatekeeper: If macOS blocks SubMiner, right-click the app and select "Open" to bypass the warning, or remove the quarantine attribute: xattr -d com.apple.quarantine /path/to/SubMiner.app

Troubleshooting ​

MPV Connection ​

Logging and App Mode ​

Performance and Resource Impact ​

At a glance ​

If playback feels sluggish ​

Practical low-impact profile ​

If usage is still high ​

Updates ​

AnkiConnect ​

Overlay ​

Yomitan ​

MeCab / Tokenization ​

Character Dictionary ​

Media Generation ​

Shortcuts ​

Subtitle Timing ​

Subtitle Sync (Subsync) ​

Jimaku ​

Platform-Specific ​

Linux ​

Hyprland ​

KDE Plasma & other Wayland compositors ​

macOS ​

See Also ​