Putting invalid velocity code in page name field when creating a page produces console errors

Steps to reproduce:

-Login
-Create a new page called C#.
-when redirected to the WYSIWYG editor, save the page.

-You well get a stacktrace in console.

Repeating the above steps but this time, instead of leaving the default document title (which is the page name), try changing it with C Sharp. You will see that the page will not throw error consoles anymore.

It also happens with user$ and #stop.