Stop SharePoint Modifying Files on its Own
SharePoint makes modifications on its own to certain Office, HTML, and other file types (even if the files are never opened). This makes it impossible to preserve document integrity or ever use checksums or file sizes to compare documents. This can also pose legal issues for users required to keep certain files. There is basically no documentation about this, though it appears to be because of property promotion/demotion. Please create a way to easily store files in SharePoint libraries without having SharePoint going through and making unilateral modifications.
I understand there may be workarounds through PowerShell or using ZIP files, but they are just that - workarounds at best - and do not inspire faith that data integrity can be preserved in the long run. SharePoint cannot be trusted with important data as long as it makes its own modifications to files as it pleases.