Not sure if this is only with Hangouts, but I am seeing this as well... I will be reading an article, then a Hangouts message comes in and Chromevox will start navigating the Hangouts convo, even though I am still in the other window... so strange

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a30d9c9ee24e8cd8edaeb724c0b2e80d91232bec

commit a30d9c9ee24e8cd8edaeb724c0b2e80d91232bec
Author: dtseng <dtseng@chromium.org>
Date: Tue Sep 13 18:55:08 2016

Ensure we check root has focus when a text changed event fires.

Text changed continues to fire in a background tab in a Hangouts session.

This causes ChromeVox to attempt to set-up an editable text handler.

The node itself has focused state, but the root (correctly) does not.

Use this as a signal to ignore the event.

We need to further qualify this to allow text changes from non-web rooted trees
because the omni bar fires text changes (without focus events) when we open a new tab.

TEST=manual
BUG= 641733 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2320583003
Cr-Commit-Position: refs/heads/master@{#418320}

[modify] https://crrev.com/a30d9c9ee24e8cd8edaeb724c0b2e80d91232bec/chrome/browser/resources/chromeos/chromevox/cvox2/background/desktop_automation_handler.js

THis has regressed in: 55.0.2880.0

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