phpBB Style Design

I use Green-Style-Slim.

Now I see that there are 2 errors.
No idea what this means, do I get problems?

Hello Hartenheer

You have changed a lot. It can not be the style. You have to check everything that has changed.
There are some errors in the W3C HTML and CSS.<meta charset="utf-8" />
I'm sorry I can not help you.
In the overall_header 2 times this will be displayed. I can not say whether derived from an extension or it is double it.
Unfortunately, I can not help you there.

The only thing I have adjusted is the header image

Hello Willem

I had a look at that again. Add the language NL in the style. Copy from the style "en" and rename it to "nl"

Thank you for the assistance.
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