Updating the Material design theme led to the effect that the colors of the header icons (i.e. the search button and the header icon) were no longer being rendered correctly. I now corrected this by adding the following lines to the CSS:
.svg-icon,
.svg-icon-title {
fill: var(--header_primary); // Fix color of header icons
}
.svg-icon:hover,
.svg-icon-title:hover {
fill: var(--primary); // Fix color of header icons
}
I believe this will be overwritten again on a next update, but to be honest, I hope the color scheme will be improved on a next update. If this is not the case, we can always put the above two lines in again.
@szhorvat, if you want to change it somethings else still, feel free to fiddle around with it. If you do make changes, it might be convenient if you report them here.