The renderer painted the paper, then blended page items with it: black
text in Color Dodge over blank paper dodged the white to white and
vanished, and other modes showed the same way. In InDesign (and in PDF,
where the page group starts transparent) the paper is not a backdrop:
over blank paper an object in any blend mode shows as it is, and only
the objects below it are blended with. On spreads that use a blend mode
the items are now drawn in their own group, laid over the paper once;
other spreads render as before.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
