chrome.tabs.captureVisibleTab is capturing elements with display: none; styling

[Jonathan Lepolt]

I'm having some issues with chrome.tabs.captureVisibleTab where it appears to be capturing a cached version of the current tab. I have a Chrome extension that allows users to capture a screenshot of the current page and send it back to our server. Our extension injects and iframe into the page to allow the user to interact with our app and the current page, and before we do the screenshot capture we hide the iframe...however, there appears to be some race condition where the tab is captured (or perhaps a cached version of it) while the iframe is still visible. I have tried some nasty hacks (like resizing the window to force a repaint/relayout), but nothing has been bulletproof. 

Any help or suggestions are greatly appreciated. Here is some code: 

$iframe.hide();
$iframe.blur();

chrome.tabs.captureVisibleTab(null, {format: 'png'}, function (dataUrl) {
  // Tell the tab we have the screenshot
  sendMessageToCurrentTab('didTakeScreenshot', {
    dataUrl: dataUrl
  });
});

The jQuery is simply setting a CSS property on the element to hide it.

[Torne (Richard Coles)]

Possibly it just captures whatever the last drawn frame was, rather than drawing a new one, and your resizing/etc is just changing the timing enough?

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[Jonathan Lepolt]

Yes, there's certainly something going on there. I have tried various setTimeout hacks, but those are brittle solutions and I'd much rather understand the fix. 

Is there a way to force Chrome to redraw the current frame before taking the screenshot? 

[Yuri Wiitala]

Perhaps webkitRequestAnimationFrame would help with some causality guarantees here?  You could do the iframe hide, wait for the "request animation frame" callback to run, and then take the screenshot?

[PhistucK]

Is there any reason why you specifically suggested the deprecated, vendor prefixed and non-standard webkitRequestAnimationFrame instead of the widely supported, standard requestAnimationFrame?

☆PhistucK

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[Yuri Wiitala]

I was not aware it had been promoted.  I am now, thanks.

[Juraj M.]

So did you tried the `window.requestAnimationFrame`?

Because I did and it didn't help. I need to use like 100 ms delay in order to take updated screenshot.

Or have you found another solution?