More Techniques From the F2F From Me

3.10.7 and 3.10.8 viewport on request and viewports do not grab focus

Intent:
Unexpected focus and viewport changes can be disorienting for all users, requiring time and effort for the user to orient to the change.  These success criteria are intended to allow the user to be in control of when viewport changes happen so the user can orient to the changes in a predictable fashion.
Example:
A web page is loaded in the browser that triggers a secondary page (typically known as a pop-up) to open.  The user agent presents the user with the initial page requested and an alert that additional content is available.  The user can choose to have this pop-up content shown or not, remaining in control of what is displayed in the user agent's viewport. A user agent may also be configured so that pop-ups do open automatically because the user has chosen to automatically have this content available.  The user has a setting however to configure pop-ups such that they open in the background.  Hence when visiting a web page with this secondary content, focus remains in the primary viewport with the initial page content requested.  The user agent alerts the user that secondary content is available in another viewport and the user can activate this viewport on request, perhaps with a click on the notification mechanism.

3.10.9 viewport on top
Intent:
The purpose of this item is to ensure that the active viewport is always available to the user due to the multiple ways the user may be accessing it.  Assistive technology for example keys off of the foreground window to report what is happening to the end user.
Example:
The user agent has multiple viewports to convey the status of what is happening.  A file download may be in progress with  status displayed in one viewport while a web page is being read in a second.  The user wants to determine the file download status so switches to the viewport displaying the file download status.  The viewport becomes the top most window in the user agent.

3.10.10 close viewport revised example
Intent: Put the user in control of what viewports the user agent has opened.
Example:
A user has multiple viewports open such as from a user agent that supports tabbed browsing and is finished viewing content in one or many of them.  The user activates a close button on the viewports that are to be closed and they are closed by the user agent.  This reduces distractions from undesired viewports being opened for the user.

3.10.11 Same UI
Intent:
Users orient themselves to a browsing environment with a variety of techniques.  This success criteria is designed to ensure that the user does not have to learn multiple strategies to use the browsing viewport.
Example:
An individual using magnification software may know that web content begins one inch from the top of the screen in the user agent and has magnification software configured to present content starting at this location.  Offering the ability to have all viewports open with the same user interface means the user can quickly focus on the web content of interest without having to orient to different UI configurations each time a viewport opens.

3.10.12 Viewport Position revised example
Intent:
This criteria targets the ability for a user to easily understand where they are located relative to the total content available for rendering and the amount of content relative to the total being displayed.
Example:
A user navigates to a lengthy web page and begins paging through the content.  A scroll bar visually indicates the position within the content as the user pages and also that with each paging action only a small portion of the content is being rendered. Another user accesses this web page with a screen reader and has the percentage that the page is scrolled communicated by the screen reader because the user agent makes information from the scroll bar available programmatically.