Hide the delete button in the annotation toolbar

To hide the delete icon from the toolbar in Nutrient, you can use the individual public CSS class selectors for each toolbar element:

.PSPDFKit-Text-Markup-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Rectangle-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Ellipse-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Polygon-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Polyline-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Line-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Ink-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Text-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Note-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Image-Annotation-Toolbar-Button-Delete,
.PSPDFKit-Stamp-Annotation-Toolbar-Button-Delete {
  display: none;
}

Or, you can try to match part of the selector:

.PSPDFKit-Annotation-Toolbar [class*="-Toolbar-Button-Delete"] {
  display: none;
}

You can see the complete list of available public CSS classes for toolbars in our API reference.