Firefox desktop-only browser extension for basic HTML5 video control

Install extension here

Features

• HTML5 video playback speed control
  • speed multipliers range from 0.05x to 128x
  • can modify speed value individually for each video
  • stores latest value separately for each site
    • if you open a new video on same site e.g. Youtube, it uses this shared value as default
    • each site tracks it's own speed state -> Youtube and Twitch speed stays separated
• customize step lengths for seeking and speed (defaults are 5s and 0.25x respectively)
• take screenshot from current video frame and copy it to clipboard
• simple popup UI where you can customize settings and hotkeys.
  • hovering mouse over labels displays a short info string for each

Permissions

This extension requires following permissions from user:

• storage -> allow use of browser local storage to store and retrieve website-specific speed values + global seek/speed steps and hotkeys.

• clipboardWrite -> allow taking screenshots from current tab's main video and copy them to clipboard

• tabs -> required for continuous synchronization between UI and content script. In particular

  • tabs.query is used for easily identifying active browser tab in the current window
  • tabs.sendmessage allows communication with content script (control.js) inside the current tab. Because UI and script code lives separately, they can realistically only communicate through messages or local storage changes. Messages are used because they
    1. are faster
    2. provide feedback to UI when needed (request-response)
    3. ensure content scripts are executed in correct tab context

  Exact use cases:

  • retrieve and apply playback speed for the active tab

    • this enforces same speed value between videos e.g, when using a Youtube playlist, auto-apply latest state onto next video

  • maintain site-specific speed settings using hostname as identifier

  • synchronize UI with active video tab: updates domain name and speed slider/input fields

  • send messages to call scripts and perform speed change, step forward/backward or take a screenshot.

    For these reasons, "tabs" is used over "activeTab". As "activeTab" only gives temporary access after user's action, it won't allow sending queries or performing data synchronizations autonomously in the background which this extension relies on.

    In conclusion:

    • "tabs" permission is only used to create a fluid interface between UI and active browser tab
    • browsing history is not collected or stored
    • data from inactive tabs is not accessed
    • active tabs will only access and modify settings data from user's local browser storage. Extension will never collect, persist or send forward any personal, user-identifying data

Issues

If you have any questions or bugs, please report them by creating a new issue.

Current:

• code uses key string values instead of keycodes. This could cause conflicts on different keyboard layouts
• when updating hotkeys, arrow keys seem to sometimes just break and refuse to register. Haven't had this happen with other keys, however
• despite attempting to override default behavior of arrow key seeking controls, sites such as Youtube and Twitch still include their own values in addition to user's seek value.
  • for example: setting seek to 10s, having forward hotkey as "Right" then pressing right arrow -> Youtube video forwards 15s instead of 10s.
  • using anything else than default left & right arrow for seeking works as expected