Hi Matthew,
Thanks for your post. Before moving on, please verify if you have disabled the tablet mode, registry HKCU\Software\Microsoft\Windows\CurrentVersion\ImmersiveShell\TabletMode is set to 0. Based on my research, this issue seems to occur more frequently when users flip the keyboard in Tablet mode. Basically, the OS ignores your settings and displays check boxes next to all items listed under File Explorer.
As a workaround, you can disable Tablet Mode. While this may not be the ideal solution, especially if you really need to use Table mode, do give it a try, and check if you notice any changes.
Best Regards,
Ian Xue
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