ACTION-1574: Propose wording for a browser and assistive technology note for example pages

Following is proposed template text for a standard note template to include on each example page.

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Note:

This example is designed to work with browsers and assistive technologies that support the ARIA 1.0 features used in the example. At the time the example code was developed, compatibility was verified with the browser and assistive technology combinations listed below.

While ARIA places requirements on browsers, and to a lesser degree on assistive technologies, for support of ARIA roles, states, and properties, ARIA does not specify details of the user experience. So even among supporting technologies, behaviors that effect the nature and quality of the user experience can vary significantly both among the technologies and from release to release of a given technology.

Browsers and assistive technologies expected to be compatible with this example code include:
* Firefox X used with NVDA X, JAWS X, ...
* Internet Explorer X used with NVDA X, JAWS X, ...
* Safari used with VoiceOver on IOS X
* Safari used with VoiceOver on OSX X
* ...

Typically, later versions of the above technologies will provide equivalent or better support.
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overcome by events