* Client-Side Metrics Include
* Wiki: https://tiny.amazon.com/cpso0wg6
* Needs to be included at the top of pages because it tracks latency--
* ue_t0 needs to be as close to body load as possible.
* - ue.tag maps to URLType dimension of OnlineQueryLog in PMET. Because we cannot add
* custome data to other dimensions in PMET through CSM, we are replicating it thrice to
* cover each store, page type, and the intersections of the two.
* - Whitelists are listed in the usage guide:
Clockworks, chapter 4: 'The Whispering Iron.'
The tamers of The Tempest -- Rendell Locke, Dodge Caravaggio, and their friends -- descend into the Drowning Cave to open the Black Door, hoping to get their hands on some of the fabled whispering iron, the material from which all of the keys are forged. And everything goes according to plan! Not.