Currently, MathJax hides children of its output root via aria-hidden but links remain in the tab order, i.e., users can then tab to an element that's not in the accessibility tree. While UAs apply conflict resolutions rules, it's not great to get errors for this kind of thing.
I realize that in v3, this may be necessary as the links become inaccessible by keyboard otherwise. But perhaps with v4 links can be removed from the tab order since the walker will become the default.
Currently, MathJax hides children of its output root via aria-hidden but links remain in the tab order, i.e., users can then tab to an element that's not in the accessibility tree. While UAs apply conflict resolutions rules, it's not great to get errors for this kind of thing.
I realize that in v3, this may be necessary as the links become inaccessible by keyboard otherwise. But perhaps with v4 links can be removed from the tab order since the walker will become the default.