Examples to Understanding 3.3.4 Error Prevention?

[Ignacio-de-Loyola]

Is it against accessibility if there is no cancel button(e.g. X) in a dialog without cancel function as in the example above? The only way to return to the previous step is to use 'Back button' after switching screens.

In a practical case, the two buttons on the bottom ('No, Thaks' and 'Payment') are the means to move on to the next step in the dialog below. In this case, the only way the user can cancel is by using the ESC key. In this case, is it against accessibility because it cannot be reversed?

[patrickhlauke]

converted to a discussion, as (very high-level) question is not about the spec itself.

[patrickhlauke]

The only way to return to the previous step is to use 'Back button' after switching screens

if that has been implemented correctly, that's possibly a reasonable approach. however, in most cases (such as that bootstrap-looking modal you have there) the back button doesn't actually close the modal as such, but navigates to the previous page in the browser's history, so it's not equivalent to an actual close control.

and just relying on the user being able to press Esc relies on the fact that they have a keyboard, which may not always be the case (particularly on mobile/tablet scenarios), so probably not a good approach either.

[Ignacio-de-Loyola]

@patrickhlauke Is what you said 'just a bad approach(UX), not against accessibility' correct?