Keyboard focus goes into embedded iframe element

[Satya Minnekanti]

Steps to reproduce

1. Open Media embed sample ​http://sdk.ckeditor.com/samples/mediaembed.html
2. Delete existing data & add few paragraphs of text
3. Embed a video using folowing URL ​https://vimeo.com/86541796
4. Video embedded and focus is on video.
5. Press Right arrow ke to focus back to editor body.
6. Press TAB key

Expected result

Focus goes out of editor body and focs on next focusable element out of editor

Actual result

Focus goes to controls inside video and JAWS reading all controls but user can't play it. Same thing happens when user Shift + TAB back in to editor body. This is Accessibility Violation

The Video controls should not be Accessible at all since user can't play video with mouse or keyboard & TAB key is used to navigate in & out of editor

[Jakub Ś]

I think invalid link was attached in point three but I can confirm this ticket.

I have attached default youtube link from sdk sample and Right Arrow + Tab has really moved focus back to widget. Next tab has moved focus to youtube video control (play button) and finally third focus has moved focus out of editor.

[Tomasz Jakut]

The problem seems to be caused by native browsers' behavior: they put iframes into page's focus list and allows to navigate inside the iframe. Adding [tabindex=-1] to the iframe prevents that default behavior (as it removes the iframe from page's focus list).

I've added simple regex to the JSONp callback that finds iframe opening tag and adds [tabindex] attribute to it.

Pushed fix to ​branch:t/14538.

[Marek Lewandowski]

Proposed solution is enough to fix the problem, actually all we want to do is to remove fetched iframes from the focus list in our cE.

Fixed with ​git:71e7ca7, merged to master.