Add subtitles to any HTML5 video sites such as Youtube, Netflix, Amazon Prime Video, Disney+, HBO Max and other stream sites.
- By:
- stefan.breitenstein
- Daily users:
- 2,243+ 12
- Rating:
- 3.77 (13)
- Version:
- 6.3.8 Last updated: 2023-10-02
- Version code:
- 5631238
- Creation date:
- 2022-05-18
- Risk:
- Moderate risk impact Low risk likelihood
- Permissions:
- activeTab
- storage
- https://*.plus-sub.com/*
- https://gqlos.plus-sub.com/*
- https://*.opensubtitles.org/**/*
- https://*.opensubtitles.com/**/*
- webRequest
- activeTab
- Size:
- 657.85K
- URLs:
- Website
- Full description:
- See detailed description
- Source:
- Firefox Browser Add-ons
- Updated:
- a day ago
Ranking
Other platforms
User reviews
Pros
- Works well for streaming videos without ads, especially on sites like bilibili.
- Allows playing local subtitle files over remote videos, enabling subtitles where none exist.
- Simple and effective for movies missing subtitles.
- Works perfectly with many useful features.
- Helps users watch videos with missing subtitles by combining video and subtitles from different sources.
Cons
- Subtitles get out of sync when videos have ads because the add-on does not adjust subtitle timing for ads.
- No built-in way to adjust subtitle offset time (only minor adjustment available) to fix sync issues.
- When subtitle font size is increased, two-line subtitles may overlap, reducing readability.
- Doesn't work on certain sources/websites, possibly due to compatibility issues.
Recent reviews
by Rob Bednark, 2025-04-05
by 远离中共邪教快退出党团队, 2025-03-29
by 敬念法轮大法好远离瘟疫, 2025-02-25
Extension safety
Risk impact
Open Subtitles requires a few sensitive permissions. Exercise caution before installing.
Risk impact analysis details
- High Allows the extension to observe and analyze traffic in flight for the selected hosts.
- Low ******* ****** ** *** ********* ******** ********************
Risk likelihood
Open Subtitles has earned a fairly good reputation and likely can be trusted.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
- Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
- Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
- Good **** ********* *** **** **** *******
Upgrade to see full risk analysis details
Compare add-ons
- Compare Open Subtitles vs +Sub
- Compare Open Subtitles vs Subs Translate
- Compare Open Subtitles vs Substital
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