Subly — PiP with Subtitles That Just Works

About

Subly puts any video into a floating Picture-in-Picture window — and 
brings the subtitles with it.

Most PiP extensions drop your subtitles the moment the video floats. 
Subly doesn't. It reads the subtitle track that's already enabled in 
the player and mirrors it into the floating window automatically. No 
re-enabling. No copy-paste. No setup. Just click the toolbar button 
(or press Alt+P) and your video floats — subtitles and all.


——— WHY SUBLY ———

If you watch videos with subtitles and want to multitask — reading an 
article, writing in another tab, or just keeping a video on screen 
while you work — you've hit the same wall: the moment you pop the 
video out, the subtitles vanish. Chrome's built-in PiP has no subtitle 
support. Other extensions ignore the problem entirely.

Subly exists to fix exactly that.


——— WHAT IT DOES ———

▸ Picture-in-Picture with subtitles
Pop any video into a floating window that stays on top of every other 
tab and app. The subtitles you already had enabled in the player appear 
in the floating window — automatically, every time.

▸ Works on every site
Subly is not built for one platform. It works on any website that plays 
video — streaming sites, course platforms, news sites, sports streams, 
embedded video players, and everything in between. No list of supported 
sites, because the list is every site.

▸ Works inside embedded players too
Many sites load their video player inside a separate embedded frame — a 
technical boundary that breaks most extensions. Subly handles this 
transparently. It detects the video wherever it lives on the page and 
still brings the subtitles through.

▸ Automatic subtitle detection
Subly reads the subtitle track the player is already using. If you have 
English subtitles turned on in the video player, those same subtitles 
appear in the PiP window. There is nothing to configure, no subtitle 
file to upload, and no account to create.

▸ One click or one shortcut
Click the Subly icon in your Chrome toolbar. Or press Alt+P. That's the 
entire workflow. Click again to close PiP and return the video to the 
page.

▸ Customise how subtitles look
Open Subly's settings page to adjust font size, font family, text 
color, background color, background opacity, subtitle position (top or 
bottom of the PiP window), and edge style (drop shadow, outline, or 
none). A live preview updates as you change each setting.


——— WHO IS IT FOR ———

→ Language learners who need subtitles visible while taking notes in 
  another window
→ People who watch lectures or courses while doing other work
→ Anyone who watches foreign-language content with subtitles enabled
→ People with hearing difficulties who rely on captions
→ Anyone who has ever lost their subtitles the moment they clicked PiP


——— HOW IT WORKS ———

When you activate Subly, it detects the video on the page — including 
inside embedded players — and opens Chrome's native Picture-in-Picture 
window. At the same time, it reads the subtitle track that is active in 
the original player and renders those cues as an overlay inside the 
floating window. If the player updates the subtitle text, the PiP 
window updates too, in real time.

For videos inside cross-origin embedded players (a common setup on many 
streaming and content sites), Subly uses a canvas-based approach that 
composites the video and subtitles together so they travel into PiP as 
a single stream.

No servers involved. Everything happens locally in your browser.


——— PRIVACY ———

Subly collects no data. It does not track what you watch, where you 
browse, or what subtitles appear on screen. The only thing it stores is 
your subtitle display preferences (font, size, color), saved locally in 
your browser using Chrome's storage API. Nothing ever leaves your 
device. No account required. No sign-in. No analytics.

Full privacy policy: https://github.com/y000yal/subly/blob/main/PRIVACY.md


——— PERMISSIONS EXPLAINED ———

Subly requests access to all websites. This is required for its core 
purpose: detecting the video and reading the active subtitle track on 
any page you visit, including pages that load their video player inside 
an embedded frame from a different domain. Without this permission, 
Subly would only work on a fixed list of sites — which defeats the 
point. The injected code is completely inert until you activate the 
extension by clicking the toolbar button or pressing Alt+P.


——— OPEN SOURCE ———

Subly is open source. You can read every line of code at:
https://github.com/y000yal/subly