demo · v130

meeting → chat context switch

The chromestatus motivation: "if the new window is semantically unrelated to the previous window, such as if it is a new VC, then the developer can use this parameter to provide a hint to the user agent that this window might be better opened in its default position / size instead." Walk a real two-context journey — open a big video-call PiP, close it, then open a small chat-thread PiP — and watch how preferInitialWindowPlacement changes the second open.

requires Document PiP (desktop) window.documentPictureInPicture is desktop Chromium only. The probe below shows support and lets you actually open the windows if available; the journey explanation works in any browser.

the user journey

1. open VC PiP
requested 640×360
→
user drags it to 980×550
browser caches that size for this origin
→
2. close VC PiP
meeting ends
3. open chat PiP
requested 360×500
→
browser sees cached 980×550
reuses that size by default
→
chat opens at the wrong size
looks empty / awkward

two outcomes

without preferInitialWindowPlacement

requestWindow({width:360, height:500})
→ browser opens at 980×550 (cached from VC)
→ chat thread is dwarfed in a huge window

preferInitialWindowPlacement: true

requestWindow({width:360, height:500, preferInitialWindowPlacement: true})
→ browser opens at 360×500 (requested)
→ window is sized for the chat thread

try the real journey

1. video call

big window — full speaker tiles + chat sidebar
requested: 640×360

2. chat thread (legacy)

small window — single conversation column
requested: 360×500

3. chat thread (new)

same as 2, but with the new option
requested: 360×500 + preferInitialWindowPlacement
probing…

the code

// 1. The video-call PiP — let users move/resize it; bounds are cached.
const vc = await documentPictureInPicture.requestWindow({
  width: 640,
  height: 360,
});

// 2. Later, after the call ends and the user opens a chat thread:
const chat = await documentPictureInPicture.requestWindow({
  width: 360,
  height: 500,
  preferInitialWindowPlacement: true,  // ignore the cached VC bounds
});

// Without the new option, `chat` would open at 980×550 (the size the
// user dragged the VC window to), making a chat thread feel cavernous.

see also