Second Add Page in Chrome hangs

I’m getting this problem on both local and remote hosts.

When I select the second successive Add Page:

The second request invariably fails with Google Chrome. There’s no CPU activity. It just seems as if Chrome has forgotten about it.
It takes about a minute to get the page with Firefox.
It works fine with Internet Explorer 11.
In Chrome, if I Add Page, move to another page, like Themes, and then go back to click Add Page again, that page appears as expected.

I’ve cleaned Chrome’s cache and it’s made no difference.

Can anyone help identify the cause?