Warn users when links open new windows
When a link opens a new window or tab, say so in the link text itself. Opens in new tab, inside the words the link is made of. W3C attaches H83 to one criterion, 3.2.5 Change on Request, which is Level AAA, and lists it as sufficient there for the pop-up case. It is worth being straight about what that means. Warning people about a new window is not a Level A obligation. A silent target=_blank still breaks the back button and forks somebody's history without telling them, so we raise unannounced ones in every audit as a usability finding rather than a conformance one. There is an argument for the target attribute that rarely gets made. It is machine-readable, so a browser can warn a user itself and can be configured not to open the window at all. And the strongest position is still W3C's own one-liner. Leave the target off and let the user decide.
How we find it in an audit
Every target=_blank on the site is a fast automated inventory. Then we read each accessible name looking for the warning, and watch for the pattern that fails quietly, which is an external-link icon with no text equivalent doing the announcing.
How affected users experience it
Activate the link and nothing says a new window opened. The first sign is the back button doing nothing, which reads as the site being broken rather than as a second window existing somewhere out of view. The old page is still there and nobody said so. Readers with cognitive disabilities lose the same thread for the same reason, because the history they were relying on has quietly split in two.
Passes vs. fails
Passes
<a href="https://partner.example" target="_blank">Partner portal (opens in new tab)</a>Fails
<a href="https://partner.example" target="_blank">Partner portal</a>How this gets tested
The W3C publishes test rules that define what a checker looks for here.
- Meta element has no refresh delayA tool can check this
- Meta element has no refresh delay (no exception)A tool can check this
Other ways to satisfy this rule
16 guides on this site are filed under 3.2.5 Change on Request. W3C lists this one as sufficient for that rule when used for including pop-up windows, so the condition is part of the test rather than a footnote to it.
- G76sufficientUpdate content only when the user asks
- G110sufficientMake client-side redirects instant, not timed
- H76sufficientMake meta refresh redirects instant, never timed
- SCR19sufficientNever change context when a select changes
- SCR24sufficientOpen new windows only when the user asks
- SVR1sufficientRedirect on the server, not with a timed refresh
This guide is our interpretation of W3C technique H83: Using the target attribute to open a new window on user request and indicating this in link text. W3C publishes its techniques as guidance rather than as the standard, and says so on every one of them. The success criterion is what conformance is measured against, and a technique is one documented way to meet it.