Strange X / page icon in Edge

[gwbonline]

I just finished a new website and I noticed some strange 'X' in the header image when viewing the site in Edge on Windows 10. In Edge for mobile phones it is a page icon. I don't know what this is and how to solve it. Maybe I'm overlooking something really simple. Can someone point me in the right direction?

An example can be seen on:
beta.kaandorpinterieurbouw.nl (view the blue header image)

 

[dnbrealm]

Sure that is a missing image icon, check your code for any images that aren't linking properly.

 

[gwbonline]

Thanks! It was a missing image (empty img tag) that caused this issue. Solved!