Background: Microsoft Edge has a "Pick up where you left off" feature when a user is reading a PDF in the browser. This works well when the user opens a tab directly to the PDF - if the user scrolls to the 15th page, closes the tab, and then opens it again later, Edge automatically takes the user back to the 15th page. This works too if the user opens different PDFs in different tabs - Edge remembers the index for that specific PDF.

The problem is though when those different PDFs are opened within an iframe on a single webpage via Javascript. Opening one PDF, scrolling to page 15, closing that iframe (JS removes that iframe from the DOM), then opening a different PDF in an iframe will open that other PDF to page 15 also, which it shouldn't. We want to maintain a separate cached index for each unique PDF.

It seems that Edge stores PDF index against the URL in the users browser window, not against the URL that appears in the iframe.

I understand this setting can be turned off within the browser, but I'm looking for a developer solution to prevent this from happening for users on the site.