v4.0.0-rc.4: client-side explorer breaks links on padding

[pkra]

Via AmerMathSoc/mathjax-xhref#20.

The extension creates links with some padding. This breaks links when the explorer is active. It seems enough to do this manually, e.g. <mpadded height="+4px" depth="+4px" width="+4px" lspace="2px" href="//google.com" data-ams-ref="type"><mi>c</mi></mpadded>.

Neither clicking nor keyboard walking+activation seems able to trigger the link when the explorer is active (but both work when speech and braille are disabled).

[dpvc]

I've made a PR that addresses the problem. MathJax was assuming that the direct parent of the selected DOM node was the <a> node for the link, but that isn't always the case (as your example illustrates). The PR causes MathJax to look higher up in the DOM tree for the <a> node in that case.

[dpvc]

Fixed in v4.0.