Change on Request

Understanding WCAG2.0

It is desirable that all operations that can cause some change in the situation are controllable by the user. As long as 3.2.1 and 3.2.2 are cleared up, we will aim for this success criterion naturally, but as far as possible, leaving the chance of change to the user is an important point of this success criterion.

If for some reason there is a behavior that automatically causes some change in the situation, it is necessary for the user to be able to stop the change.

The interesting thing is the reference to Understanding about target = _blank. On the other hand, if it is explained in the link text that "Open in a new tab (window)", it is said that it is okay to do this, but it is better if you can not specify by target if possible. There is a case where it is convenient for most users to have target designation around here, which is quite troublesome.

Principle Understandable Information and the operation of user interface must be understandable.
Guideline Predictable Make Web pages appear and operate in predictable ways.
Criterion Change on Request
(3.2.5 AAA)
A change in context only occurs at the request of the user, or a mechanism for stopping such change is available.

URL of Techniques for WCAG 2.0