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Using the TAB key allows users to move forward through each button on the player: Play/Pause, Mute Toggle, Stream Quality, Create Thumbnail, and Fullscreen. As each element is focused it will be surrounded by an outline, in order to enhance its visibility from other elements on the page.
Each button can be triggered by pressing the ENTER key.
The Stream Quality selector will allow the user to use the TAB button to choose between the available stream qualities (defaults: High, Medium, Low for video and High, Medium for audio) by pressing the TAB key to highlight the appropriate button and then pressing the ENTER key to select the button.
When the player controls have focus the user can toggle between Play and Pause by pressing the SPACEBAR.
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