Formatting Dialogs

When someone enters an incorrect username or password, a login error occurs. I have been able to fix using html some of the error messages that are in the dialog tab, however I can’t seem to find there to change/update this error message.

As you can see, it overwrites the header. If you go to the link provided, and type in gibberish for the username and password you can see the error.

Your help is appreciated.

Thanks,

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