Weird: 1 user can't see the content on a Modern page

I have one user who is unable to see the content on the Modern pages in one and only one Site Pages library. She has permission to the page, can click on it and open it, but the page itself opens blank. There are various web parts on the page and everyone else as far as we are aware have no issues with seeing them, but this one user cannot. Furthermore, she CAN see the content on pages in other site collections, AND if we create a new page in the problematic library, she can see that. And she can navigate around other lists and libraries in the same site just fine. But pages in the Site Pages library that were already created when the issue began have issues.

We've had her login to the site from other PCs and from her smartphone, same issue occurs. Other people who login to the site from her own PC do not have the problem.

Naturally my first thought was permissions, but everything I've looked at checks out. She has Read permission level on the Site Pages library as well as to the lists and libraries that are referenced on the page via web parts. I even checked the Master Page gallery, Web Parts gallery, Site Assets library, and Style Library. All fine.

However, it still has to be related to her account, given that she experiences the issue across machines and browsers, and other people don't with the same equipment.

The only external factor that may be involved, though I can't figure out how, is that we are in the middle of a tenant-to-tenant migration, and I suppose it's possible something was messed up in AAD. But again we checked her license and service toggles, and once again everything looks fine.

Any thoughts? This one is pretty perplexing.