In certain cases, when the Reading view has a horizontal scroll bar, it also ends up as a picture in the PDF export. That obviously looks strange.
Specifically, this happens to me when there’s a long inline formula (the type between single $ characters), as in the attached example: test.md (113 Bytes)
Although this is a long formula, its rendered version easily fits in the available horizontal space. And even if it doesn’t, it should be truncated in the PDF, without a picture of a scroll bar. This is how the PDF comes out: test.pdf.zip (16.3 KB)
This happens consistently. Here is a screen recording from the generation of the files I attached above, in a fresh sandbox vault: Scrollbar.mp4.zip (1.3 MB)
As you can see, Reading view gets a horizontal scrollbar that it doesn’t really need, and that bar makes an appearance in the PDF.