The featured image in the Twenty Twenty theme goes under the navigation if the page is using the cover template. Make sure there’s enough contrast between the image and the text that’s on top.
I put a background behind the navigation to give it more contrast
.page-id-232 .header-navigation-wrapper {
background-color: #405693;
padding-left:1em;
padding-right:1em
}
The page title, the H1, goes on top of that image too. In this case the contrast is a bit low, so I gave it a shadow.
.page-id-232 h1{
color: white;
text-shadow:
-1px -1px 0 #004466,
1px -1px 0 #004466,
-1px 1px 0 #004466,
1px 1px 0 #004466;
}