SSynch Firefox

SSynch

Watch videos together in sync. Create a room, share the code, and everyone's player follows — on any site.

Features & Capabilities

Watch together, actually in sync.

Starting a film "on three" never works. Someone's stream buffers, someone pauses to get the door, and twenty minutes later everyone is a different distance into the same film.

SSynch keeps every player on the same moment. One person creates a room and picks the video; everyone else joins with a six-character code, and their player follows.

How it works

Click the SSynch icon and hit Create room. Share the six-character code with whoever is watching. Open your video and hit "Select video on this page". Everyone else's browser opens the same page and locks onto the same video. Watch. Play, pause and seek from any side — it applies to everyone. What it does

▸ Works on any site. SSynch attaches to the video player itself rather than to a hard-coded list of streaming services, so it behaves the same on a big streaming service, a self-hosted file, or a lecture recording.

▸ Corrects drift as it goes. No two browsers play at exactly the same speed. Rather than only syncing when somebody clicks something, SSynch keeps comparing positions and correcting — an imperceptible speed nudge for a small gap, a seek for a large one — so you don't quietly drift apart over a two-hour film.

▸ Accounts for lag. Playback positions are corrected for the round-trip delay to the server, so joining late or jumping to a new scene doesn't leave you a second behind everyone else.

▸ Anyone can control it. Pause to get the door, rewind for the line nobody caught — every participant can, not just whoever started the room.

▸ Stays out of the way. A small widget shows who's connected and whether you're in sync. Drag it anywhere, collapse it to a single button, and it stays visible in fullscreen.

▸ Survives real life. It reconnects on its own after a dropped connection, a page reload, or a long pause, and re-finds the video if the player rebuilds itself mid-session.

▸ Nothing to sign up for. No account, no email, no profile. Generate a code and go.

What you'll need

Everyone needs SSynch installed, and everyone needs their own access to whatever you're watching. SSynch synchronises playback — it does not stream, share, or re-broadcast video. If a site needs a subscription, each person still needs their own.

It works with standard HTML5 video players, which covers most of the web. Some heavily customised players behave differently, and sites that block extensions outright won't work.

Privacy

No accounts, no analytics, no tracking, no third parties. To keep a room in sync, SSynch sends the address of the page the host shares, a description of which video element to control, and the playback position. That's the whole list — no page content, and nothing about any other page you visit. Room data is deleted 24 hours after a room was last used. Full policy linked below.

User Growth & Download Statistics

Manifest V3 Add-on
By:
emilvdijk
Daily users:
1
Version:
1.0.1 Last updated: 2026-08-08
Version code:
6397016
Creation date:
2026-08-05
Risk:
High risk impact High risk likelihood
Permissions:
Host permissions:
  • <all_urls>
Content scripts matches:
  • <all_urls>
Size:
39.78KB
Email:
em*****@gmail.com
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-08-15
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
emilvdijk
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/ssynch/
Email:
em*****@gmail.com
Website:
https://github.com/Emilvdijk/SSynch

Is SSynch Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

SSynch requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
  • Critical ****** ****** ** *** ********* ****** * *********** ******** **** ** ** *** ******* *** ****** **** **** *** ******* *****
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
  • High ****** ******* *** ********* ********* ******** ***** *** ** ********** ****** * ******** ******* *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

SSynch is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • High **** ********* *** ******** ****** *** ********** *** *** ** ****** ** *****
  • High **** ********* *** *** **** ****** ********* ********** *** *** ** ****** ** *****
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