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Popups are not a good user experience for keyboard-only /users and screen reader users and as a rule of thumb we should steer away from using themshould be avoided.
When a an automatic popup appears it does not have keyboard focus which means that keyboard only/screen reader users are unable to tab to the content within the popup. Screen reader and keyboard-only users can easily become distracted and disoriented.
When a popup unexpectedly appears it does not have keyboard focus which means that screen reader users are unable to use the TAB key on the keyboard to navigate to the content within the popup. They cannot visually see the popup on the screen, unless it's automatically programmed to completely shift the focus away from the main window. However, this would be very disorienting to screen reader users.
Unexpected and automatic popup windows should not appear without warning or notification.
Users should be provided with a mechanism, such as a link or button, to activate a new window.
Ensure that keyboard focus is visible and not obscured when a new window is opened, so users can easily identify where they are within the content. Sighted keyboard only users navigate web pages by using the TAB key on the keyboard through actionable items such as links, buttons and form controls. They rely on keyboard focus indicators (a border or outline) to let them know what item has keyboard focus. Keyboard focus indicators cannot be obscured by a popup window.
New windows should not automatically be launched, and change context, when a component receives focus.
Modal Windows
If there is no other solution than a popup use a modal window. It must be programmed in a way that allows for the following.
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