1) InDesign 16.1 (and othre versions)

2) Place an image or object. Apply a drop shadow. Pan/scroll, zoom, enable or dissable output preview

3) Consistent rendering.

4) Glitches of bands of light or dark pixels may appear over images, in transparencies and effects. These may come and go depending on resolution preview mode, zoom and/or if overprint preview is rendered. (The lines are similar to tiling lines in PDFx1a in that they are rendering glitches presumably caused by floating point calculations)

See the thread https://community.adobe.com/t5/indesign/lines-appearing-in-effects-shadow-amp-gradient/m-p/11912229#M419035