Fix #14180. Allow cross-frame use of focusin/out. Close gh-1369.
(cherry picked from commit 6d5dfa0eda2c19e8838930fafff83b596654eca2)
Manually edited for conflicts.
Revert "Fix #14180. Allow cross-frame use of focusin/out. Close gh-1369."

This reverts commit bba8366af48bd2c80c96e7a0f58b3e16fd736125.

Because cross-frame focus sucks.
Add tests for class manipulation on jQuery object containing more than one element. Close gh-1404. (cherry-picked from 35b2b94979ed3419e50b72ab3b84307269fa25e8)
No ticket. Update npm devDependencies. (cherry-picked from 95d1192d5378926e750d0494818323ff17be821e)
Fix #14459: Use jQuery.parseJSON instead of JSON.parse
(cherry picked from commit ced9d155f010bc456745a55a63ca959db9d405d3)
Fix #14379: AJAX requests on unload
(cherry picked from commit f9d41ac641dcb5a93ba8a9027476b160d8f41111)

Conflicts:

	src/ajax/xhr.js
Ref f9d41ac6: Opera-compatible form target
(cherry picked from commit d5b7139abce9dd207773531d6dcb3493c6ac0c7c)
Ref 705216dc: Synchronize ajax/xhr.js with master. Close gh-1418.
No ticket: Update style per gh-1418 comments
Fix #14190: Remove unnecessary assignment in .closest. Close gh-1411.
(cherry picked from commit 346b031af9e3b315ef351a9cc7fee56f930cf346)

Conflicts:

	src/traversing.js