Stop PDF from Automatically Resizing Pages as You Scroll in Browser View

True. But unless the document is being circulated only to a controlled reader group that is either savvy or specifically informed, you have to consider the vast number of users of these embedded, "invisible" apps that work the way they were installed, for users who either don't know their behavior can be changed or "have things set the way they like them." Reality, in other words.

Consider that some great majority of users have no idea there is more than one PDF reader — among those aware that there is a "reader" involved at all. Even among somewhat skilled users here, it's news that not all readers are the same.

Most PDF (and EPUB) readers can be adjusted to suit individual documents. Most users cannot.

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There are always workarounds, at least on most variant viewers. But every user is going to have different (probably default) settings and have either no knowledge of how to change them (or maybe even that they can), or be unwilling to do so to view one document with outlier formatting.

The OP needs to choose between a more standard page layout that will display more normally on a majority of viewers, or accept that some users are going to have to deal with a wonky experience. (Or perhaps embed instructions for correcting a wonky view, but that's probably not an optimal path.)

Or — as was common with web pages for so long — note that the doc "is best viewed using Adobe Acrobat Reader."

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