I’m using OC 3.0.74 and when extending the Page CMS Settings popup according to this article:
https://octobercms.com/blog/post/introducing-cms-editor-extensibility-api
I’m getting a weird grey background on the field that makes imposible to read the field content as the text is the same color as that background. Please see image:
As I was inspecting the css code, I saw it can be resolved setting:
.component-backend-inspector-panel .component-backend-inspector-controlhost .inspector-control.placeholder {
background: transparent;
}