A bunch of new documents were found a few weeks ago. Story below.
But it contained presidential SCHEDULES - things that are classified at the time but are then unimportant afterward. An absolute nothingburger.
I suspect that was what Pence had; it might be what Biden had too, we don't know. These guys don't worry about what happens to their schedules after the fact - and they shouldn't.
Unless we know the level of classification for any of these documents, we can't know if this is serious or not.
Link: https://www.cnn.com/2023/02/24/politics/trump-classified-documents-maralago-eluded-fbi/index.html