MS Word in the web (via onedrive)
You are comparing apples to oranges. The onedrive version is the free, crippleware version. The 
paid version that companies use does include the functionality to save as with the older binary 
formats. [1]
Until recently, my company had a group policy to save as in these MSO binary formats. LibreOffice 
had then and continues to have much better compatibility with these binary formats than the newer 
OOXML versions.
[1] 
https://support.office.com/en-us/article/use-compatibility-mode-to-work-with-different-versions-of-powerpoint-bc87ca23-4208-4d58-9c01-3a38a84c16e0
Context
- Re: LibreOffice and old Microsoft Binary file formats. · Luke Benes
 
   
 
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