Poller.js should be checking focus on the window not the document.

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 6.2.X EE, 7.0.0 Alpha 2
• Fix Version/s: 6.2.4 CE GA5, 6.2.X EE, 7.0.0 Alpha 2
• Component/s: Frontend Infrastructure
• Labels:
  • liferay-fixpack-portal-76-6210
• Branch Version/s:
  6.2.x
• Backported to Branch:
  Committed
• Story Points: 12
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal-ee/pull/11666

When multiple browser windows are open to Liferay, Poller freezes polling on the window that is not focused. In certain browsers, poller fails to unfreeze itself when you focus the tab, because it checks document focus which does not always fire.

Firefox: A.getDoc().on('focus') fires whenever the tab gets focused.
Chrome: A.getDoc().on('focus') only fires when focusable elements are clicked.
Safari: A.getDoc().on('focus') never fires.
IE11: A.getDoc().on('focus') only fires when clicking a focusable element, or switching focus from a different application. It does not fire when switching tabs.

All of these browsers consistently fire A.getWin().on('focus').