I want to display a custom error page:
<!doctype html>
<html>
<head><title>400 Bad Request</title></head>
<body><h1>400 Bad Request</h1>
The grob must be in the frobber.
</body>
</html>
Unfortunately, Internet Explorer ignores the response sent by the HTTP server; hiding my page and showing their own:

How can I convince Internet Explorer to show the page the user was sent?
Edit Chrome began doing the same thing in 2008. People have asked for it to be fixed; but it’s marked as won’t fix.
And you can fix it using the same trick in the answer.
The solution is PADDING.
Microsoft notes in knowledge base article KB294807:
Make it bigger
So i bulk up response page to:
Problem solved.
Bonus Reading