The zoom level is set to make the PDF fit to page with the animated top toolbar shown. When it disappears, PageUp/Down scrolling no longer jumps a full page. One can still use left/right arrow to move a full page when the PDF is sufficiently zoomed out.

Ah, so if the toolbar stayed onscreen then the pagination would work correctly?

Playing around with this a bit, I think in the current version Chrome behaves mostly as desired expected.

Left/Right arrows work for paging when at Fit page to screen or lower zoom levels. Scrolls horizontally when zoomed in more.

PageUp/Down work when at Fit Page to screen level regardless of the overlay/toolbar being present, at least with the documents I was using. When at any other zoom level they jump some number of unknown units.

Space/Ctrl+Space appear to have similar behaviour to PageUp/Down.

When at a zoom level that does page advancement, for all of these keystrokes, it appears recentre if you scroll part way between pages and then hit the keystroke.

This seems reasonably good to me.

dsinclair, does this seem sufficient? Do you have an example PDF that is scrolling weirdly?

I believe the problem here was around the toolbar. The toolbar would cause the page to not quite be at the right spot and the more pages you scrolled the more you'd end up shifting the page.

I don't follow either, fit to page mode seems to be working fine. For the default mode, the page is already not the size of the screen.

Setting PDF bugs assigned to me back to untriaged so they can get re-assigned as needed.

When in fit-to-page mode, this is working fine. Therefore, closing.