Visual tab of WYSIWYG field doesn’t work in Firefox

Symptoms

In Firefox the Visual tab of a WYSIWYG field is inert, clicking in the content area does nothing, but it is possible to switch over to the Text tab, which works as expected.

There are no errors in the console.

The problem occurs because of an issue in WordPress core, resolving which should resolve this: https://core.trac.wordpress.org/ticket/52133

Workaround

The Visual tab works as normal in other browsers such as Chrome, and the Text tab can be used instead.