explorer not active after refreshing

[pkra]

Steps to reproduce:

• visit https://cdn.rawgit.com/mathjax/MathJax/2.7.1/test/sample-mml.html
• activate the explorer in the menu
  • explore beautiful, state-of-the-art rendering
• refresh the page
• focus an equation and shift+space

Expected:

• the explorer starts

Actual:

• the MathJax menu opens
• the checkbox a11y/explorer/activate is ticked but no other options are available

Workaround:

• hitting the checkbox again activates the explorer

[pkra]

Reproduced on Chrome and FF latest.

[dpvc]

It turns out that the accessibility-menu extension has a timing problem when used in a combined configuration file. The combined configuration file runs before the menu cookie is read, the menu settings aren't actually in place when the accessibility-menu code runs, so it doesn't know that the menu items have been selected, so doesn't load the needed code.

I have put a fix in the issue197 branch.

[dpvc]

==> Merged.