Inform users if new windows appear |
WAI / WCAG 1.0 Priority 2 checkpoint 10.1
Issue Description The page contains links that may cause the browser to open a new window (either via a TARGET attribute or via a javascript:window.open() instruction). If this is the case, ensure that the visitor is told that this is the behavior. If the user is not notified, then the page fails to satisfy this checkpoint.
How to check Try to avoid opening new browser windows. If this is not possible, notify the user that a new window will be opened when the user clicks on a certain link or button. For example, write "(new window)" just before the link text, within the link text, or write it in the link TITLE attribute. Another option is to systematically adopt in the site a small icon whose meaning is "new window being opened" and put that icon in the link label (set its ALT to something like "new window"). More details on Qbullets [http://www.matterform.com/index.php?page=/qbullets/index.php] (animated GIFs must be avoided).

In all cases, add a "Close" or a "Back" button to the new window that would close the new window or lead to the previous page, respectively.

Issue Explanation When the browser opens a new window, as an effect of clicking on a link or button, the environment in which the user is working changes. It changes because:

- some features of the browser itself in the new window may change. For example, the browser's buttons may be hidden completely, the geometry and position of the new window change, the new window is opened on top of the old one, or other times it is opened below;
- even if not disabled, the "Back" button of the browser does not work, since in the new window there is no "URL history" (and no previous URL).

These two factors, possibly combined together, amplify the possible difficulties experienced by visitors, especially those who are disabled or use disabling technologies. For example, if the new window is opened with the same size and position as the old one, on top of the old one, it might appear to a visitor as the same window. The visitor might interpret the fact that the Back button does not work as a bug of the browser (and might restart the browser) or a bug in the site (and might switch to another one).

For visually impaired visitors it is even worse: screen readers might not be able to tell them that there is a new window. Screen magnifiers users might have a very hard time in guessing that there is a new window somewhere and where the new window is placed.

Therefore it is crucial that the visitor is told that a new window is being opened. Obviously the visitor should be told that before opening the window.

In all cases, the new window should contain a button that leads the visitor back to the page that has opened the window (or alternatively that closes it). These buttons will work also if the new window has disabled the standard browser buttons.