Why has my Browser User Agent Extension broken suddenly?

Environment:

Agent Browser User UI (BUI) extensibility framework, BUI updates

Issue:

Extension is broken after BUI Update

Resolution:

Manipulation of the object model or DOM of the BUI workspace is done from the Extension Framework. Manipulation of the BUI workspace with the document/jQuery selector is not supported. The BUI workspace is updated weekly according to the schedule in the answer here.  Browser User Interface Updates

DOM manipulation is ineffective; as the updates for the BUI interface will modify the selector location and ID's in the workspace DOM. Causing the Document/jQuery selector to start failing.

Getting field values from the BUI workspace's is done with the getFieldValues function in the BUI extension workspace. 

Cause:

When the weekly BUI update is released the names of ID's of the workspace may change; breaking the selector. DOM objects may also move position in the DOM.

Notes:

Manipulation using the document/jQuery selector inside the BUI extension itself will function as expected

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