ASP.NET : Inline validation controls no longer red

So I had a project that I was busy migrating from .NET 3.5 to .NET 4.5.

Now I use the asp:RequiredFieldValidator controls and suddenly I noticed that the error messages were no longer in red.

I then compared the projects - no obvious .ccs changes or anything like that.

Then I compared the web.config files and noticed that:

pages controlRenderingCompatibilityVersion="3.5" clientIDMode="AutoID" validateRequest="false"

had changed to:

pages controlRenderingCompatibilityVersion="4.0" clientIDMode="AutoID" validateRequest="false"

This must have happened during the wizard that migrates the project.

Have a look at:

What's New in ASP.NET 4 and Visual Web Developer

where it mentions that validators no longer render inline color:Red styles.

Changing it back to "3.5" sorted it out.

Isn't red the international error colour anyway?

Enjoy!