Window Sill Firefox

Window Sill

Sync your tabs in one Firefox window and seamlessly have them waiting for you on your computers

Features & Capabilities

Automatically synchronize browser tabs from one computer to your others. Just open the Window Sill, and any tabs left there will open on other computers you are logged in to. Close the tab on one browser, and it'll close on the others.

Usage

First, be sure you are logged in to an account with your browser. If you're using Firefox, you can create an account here. Without this, your tabs can't be synced to the shared storage your browser account provides.

If you click the extension icon in the browser, you'll see 3 buttons.

  • Open Window: switch focus to the Window Sill; if not already open, creates a new Window Sill and opens all tabs that have been synced.
  • Sync Now: synchronizes all your tabs to the cloud. If there are new tabs on the Window Sill, placed there from a different computer, these will open now (or close tabs that have been closed on the other device). You don't have to always hit this button, your tabs should automatically sync every 5 minutes on their own. The time since the last synchronization will show in this button.
  • Activity Log: shows your tabs that have been opened or closed on previous synchronizations. I'm not perfect and neither is synchronized data storage, so if there are issues with your tabs (i.e. a bunch of tabs open or close without you expecting them to), this is where you would check to get the links to re-open.

Every tab title in the Window Sill be prefaced with 🪟. There can only be one Window Sill opened at a time.

Source: https://github.com/kevincrane/windowsill

User Growth & Download Statistics

Manifest V2 Add-on
By:
kevincrane
Daily users:
-
Version:
0.2.2 Last updated: 2021-02-09
Version code:
5179613
Creation date:
2021-02-08
Risk:
Moderate risk impact Moderate risk likelihood
Permissions:
Size:
26.42KB
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-06-14
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:
kevincrane
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/windowsill/

Is Window Sill 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.

Window Sill requires a few sensitive permissions. 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.
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.

Window Sill is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
  • Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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