Code example for visually hidden elements isn’t cross-browser compatible

[AndreasMoesch]

In the chapter about visually hiding elements the second code example should illustrate how you can toggle the visibility of visually hidden elements on focus.

Code Example: Toggling visibility of a hidden element on focus

The instruction is to use Tab to move the focus and toggle the visibility of the “Jump to content” link. This works well in Chrome but doesn’t work in Firefox (version 71) or Safari (version 13.0.4). I haven’t tested in Edge or IE.