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CaptionGo – Live Captions & Dual Subtitles version history - 10 versions

CaptionGo – Live Captions & Dual Subtitles by RabbitPair

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CaptionGo – Live Captions & Dual Subtitles version history - 10 versions
  • Be careful with old versions! These versions are displayed for testing and reference purposes.You should always use the latest version of an add-on.

  • Latest version

    Version 1.1.2

    Released Sep 20, 2026 - 3.05 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Smarter language detection: When Live Captions can't reliably detect the spoken language, it now pauses and prompts you to select a language manually instead of guessing — saving your recognition quota
    • Better Chinese/Japanese/Korean recognition: Improved accuracy when distinguishing between Chinese, Japanese, and Korean audio
    • Language re-detection on seek: Seeking to a different part of the video now restarts language detection from the new position — ideal for skipping music intros or navigating to speech sections
    • More reliable audio processing: Improved compatibility with a wider range of video formats, reducing cases where audio download would get stuck at "Downloading audio…" or fail to produce subtitles
    • Audio download progress: Now shows real-time download progress with speed (e.g. "Downloading audio… 35% (120 KB/s)") so you know exactly what's happening
    • Better reliability on slow networks: Audio download now automatically retries with optimized settings on slow or unstable connections
    • Processing progress between segments: Shows progress indicators (e.g. "Processing audio… 3/7") between subtitle segments, only when no subtitle is currently displayed
    • AI translation quality upgrade: Refined translation prompts for better subtitle coherence, larger context window (up to 30 previous lines), and video metadata (title, synopsis) now informs the translation for more accurate results
    • ASR-aware AI translation: AI translator now adapts its approach when translating speech recognition subtitles, producing more fluent results for imperfect source text
    • AI translation privacy control: New toggle in Translation Settings to control whether video context (title, URL, description) is sent to AI translation — enabled by default, can be turned off for privacy
    • Fixed video black screen when opening video file URLs directly in the browser (e.g. .mp4 links)
    • Fixed MP4 audio extraction downloading nearly the entire file for certain video formats (e.g. lecture/educational videos), now intelligently extracts only audio data
    • Fixed subtitles stopping midway through longer videos when the predownload window was fully processed
    • Fixed "Preparing subtitles…" message stuck on screen after seeking to an already-processed section
    • Fixed predownload progress indicator getting stuck and not reaching 100%
    • Fixed language selection badge not appearing when manual language selection was needed
    • Fixed translation inaccuracies caused by repeated phrases across different subtitle segments sharing cached translations
    • Fixed membership status not refreshing after browser restart

    Source code released under All Rights Reserved

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  • Older versions

    Version 1.1.1

    Released Sep 19, 2026 - 3.03 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Fixed Live Captions predownload restarting repeatedly on sites using Wistia player (e.g. online course platforms)
    • Better predownload stability — fewer unnecessary restarts, avoids re-processing already-recognized audio segments

    Source code released under All Rights Reserved

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  • Version 1.1.0

    Released Sep 17, 2026 - 3.03 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Live Captions on more sites: completely rebuilt speech-to-text engine that automatically detects audio sources from HLS, DASH, and MP4 video streams
    • Automatic video stream discovery: detects video manifests and audio URLs by monitoring page network traffic, so Live Captions works even on sites without explicit audio source configuration
    • Encrypted video support: Live Captions now works on sites using AES-128 encrypted audio, including more streaming platforms with protected content
    • Bandwidth-efficient audio download: extracts and downloads only the audio track from MP4 files instead of the full video, reducing data usage significantly
    • TikTok and hotlink-protected sites: automatically adds the correct request headers so audio predownload no longer fails on sites like TikTok that block external requests
    • Live Captions no longer shows "downloading…" or "processing…" messages once subtitles have started appearing — only errors are shown
    • Improved subtitle style isolation using Shadow DOM, preventing conflicts with complex web page styles
    • Audio predownload settings can be updated remotely without requiring an extension update

    Source code released under All Rights Reserved

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  • Version 1.0.31

    Released Sep 14, 2026 - 2.96 MB
    Works with firefox 140.0 and later, android 142.0 and later
    bugfix

    Source code released under All Rights Reserved

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  • Version 1.0.30

    Released Sep 14, 2026 - 2.96 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Prime Video control-bar button: the bilingual subtitle button now appears next to the fullscreen button
    • BBC News / iPlayer Toucan Player subtitle support
    • A+E Networks site support: HISTORY, A&E, Lifetime, and FYI
    • Paramount Avia player support for Nick and other Paramount brand sites
    • Multi-rule subtitle matching: when the primary parser fails, CaptionGo automatically tries alternative subtitle formats to reduce missed captions
    • ABC News and related sites: subtitle button in the Disney Web Player control bar with m3u8 segmented subtitle support
    • Aftonbladet TV, VGTV, and other Nordic media site control-bar button support
    • Live Captions now supports "Auto (Detect Language)" mode — automatically detects the spoken language in the video and selects the best speech recognition model, supporting 50+ languages. A two-phase detection flow quickly identifies the language and then verifies accuracy, auto-correcting if the initial detection was wrong
    • DASH segmented MP4 subtitle format (stpp/TTML) parsing support for sites like play.joj.sk
    • Rebuilt control-bar button insertion for better reliability across sites
    • Improved THEOplayer compatibility: dedicated caption detection and button placement, avoiding conflicts with generic Video.js rules
    • Updated Prime Video caption selectors for the latest page layout
    • Live Captions shows clear real-time status during language detection: detecting, verifying, and confirmed indicators keep you informed throughout the process
    • Fixed control-bar buttons being unclickable on certain Shadow DOM-based player sites
    • Fixed Live Captions not detecting or correcting when the wrong language was selected — now auto-switches to the correct language
    • Fixed DASH video predownload failing due to segment data decoding errors
    • Fixed Live Captions status icon still showing active after repeated connection failures

    Source code released under All Rights Reserved

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  • Version 1.0.29

    Released Sep 12, 2026 - 2.93 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Media Chrome player support: the bilingual subtitle button appears next to captions or fullscreen in the control bar
    • Control-bar buttons on more online video players and embed sites
    • More reliable entry button: if the control bar is missing or not ready, CaptionGo shows a corner or floating button, then switches back when the control bar appears
    • A single video on the page still gets an entry button even when the player looks small on a large screen
    • Fixed sites where neither the control-bar button nor the floating button appeared
    • Fixed the button jumping around inside some player control bars

    Source code released under All Rights Reserved

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  • Version 1.0.28

    Released Sep 11, 2026 - 2.93 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Subtitle navigation buttons: previous, replay, and next — quickly browse through subtitle content (shortcuts A / S / D)
    • Subtitle auto-pause: automatically pauses the video at the end of each subtitle line for sentence-by-sentence study (shortcut Q)
    • Copy subtitle button: copy the current subtitle text with one click (shortcut Ctrl+C)
    • Subtitle drag handle: hover over subtitles to reveal a drag handle for repositioning
    • Caption width control: drag a slider in caption style settings to adjust maximum subtitle width (50%–100%) (Pro)
    • 7 new font options: Poppins, Quicksand, Sofia Sans, DM Sans, Montserrat, Open Sans, and Lato
    • Thin (100) and Extra Light (200) font weight options — weight menu now shows numeric values
    • Uscreen video player support
    • Upgraded to variable fonts: font weights transition smoothly from 100 to 900 for a more refined look
    • Updated caption color palette with softer, modern tones for improved readability and visual comfort
    • Better multi-line bilingual subtitle positioning: subtitles no longer overflow the video bottom or get obscured by controls — multi-line content grows upward
    • Smoother caption drag interaction with improved stability
    • Better compatibility for menus and popups being hidden on some sites
    • More reliable auto-upgrade from floating button to control bar button
    • Fixed caption position showing 10% in the menu when set to 0%
    • Fixed caption position flickering on hover

    Source code released under All Rights Reserved

    Download file
  • Version 1.0.27

    Released Sep 9, 2026 - 2.97 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Crunchyroll subtitle support (Pro): Crunchyroll uses hard-rendered subtitles, so the free page-subtitle mode is not available
    • 20+ new player integrations: including Vimeo, BBC iPlayer, Wistia, ArtPlayer, NPlayer, Shaka Player, Bitmovin, Clappr, ARD/ZDF Mediathek, and more
    • Caption track type recognition: automatically distinguishes between standard subtitles, CC/SDH closed captions, and ASR auto-generated subtitles, with [CC] / [ASR] badges in the menu
    • Smart caption selection: prefers standard dialogue subtitles for translation to improve quality
    • Better button compatibility: adapts to more player layouts and Shadow DOM scenarios
    • Floating button fallback for unconfigured sites: reduces wait time for subtitle access
    • Smarter video change detection and caption caching: reduces unnecessary subtitle reloads
    • Improved subtitle recognition on Bilibili, Disney+, Hulu, VK Video, MediaElement.js, and more

    Source code released under All Rights Reserved

    Download file
  • Version 1.0.26

    Released Aug 28, 2026 - 2.96 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Better bilingual subtitle stability: automatically retries when translation temporarily fails, preventing subtitles from showing only the original language for extended periods
    • Faster subtitle recovery after seeking: bilingual subtitles reappear more quickly after scrubbing the progress bar
    • Improved SPA site support: bilingual subtitles now automatically restart after page navigation on sites like SVT Play
    • Clearer language menu labels: "Native Language" renamed to "Translate to", "Learning Language" renamed to "Subtitle Language" for better clarity
    • Fixed bilingual subtitles stopping on some sites after long periods without subtitle content
    • Fixed outdated subtitle container selectors for SVT Play
    • Live Captions (ASR) is now a PRO-only feature: Due to rising speech recognition service costs, Live Captions now requires a PRO membership. We sincerely apologize for the inconvenience. PRO members can continue using both the built-in cloud recognition and custom API key modes

    Source code released under All Rights Reserved

    Download file
  • Version 1.0.25

    Released Aug 26, 2026 - 2.97 MB
    Works with firefox 140.0 and later, android 142.0 and later
    • Netflix smart subtitle preloading: automatically downloads and caches both native and learning language subtitles simultaneously when watching Netflix, eliminating translation wait times
    • New "Learning Language" setting in the menu, with clear descriptions for Source Language, Native Language, and Learning Language
    • Prefer human-translated subtitles: when official subtitles in your native language are available, they are used directly instead of calling a translation service
    • Fixed Simplified Chinese subtitles occasionally displaying as Traditional Chinese when set as native language

    Source code released under All Rights Reserved

    Download file
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