when I created this header.php, I could check how it looks in the design view though, now I see the view like below. I used to be able to see the same header image in the design view on Wappler before. so it might be a bug??
We are currently not including (and have not included until now) the custom CSS file defined in your project settings on the content/include pages, opened separately.
We are going to improve this in our next updates