What does this yellow square mean

[Berryth]

What does the yellow square mean?

Can't find it anywhere

What does it mean?

[Jhousefavitguy]

So why does Dropbox start to sync when I click on a file that has that icon but files without that icon don't cause that? I just had a user this morning that could not open a file in their Dropbox synced files with this icon. Closed Dropbox and reopened and was able to access. That file does not sync to OneDrive either. I understand it is not a Dropbox icon by why is it there if those files are not connected to OneDrive and the fix is closing/opening Dropbox?

[Mark]

That is a OneDrive icon. So they almost certainly have the files stored in two locations. Once in Dropbox and once in OneDrive.