Both FocusSpec.html and Modality.html use GIF images to show diagrams which illustrate the description. The images look jagged, especially on High DPI screens which are common now. The images in Modality.html use dithered colours which don't look sharp even on regular displays.

All the modern browsers support SVG which is a vector format and therefore it adapts to any resolution and always looks sharp and clear.

Replacing the GIF images with SVG will make Java documentation look sharper.