I have recently had conversations with a few clients who have been experiencing issues with Sharepoint and collaborative working, where a document's styles are becoming corrupted. In particular there seem to be issues with multi-level lists. After some investigation and research it seems this could be as a result of some contributors using the online browser version of Word. I have come across a few posts on online forums that suggest this is an issue Microsoft are aware of and that they are investigating.
I would suggest that in the meantime, if you have documents that are being worked on collaboratively, it would be a good idea to request that all your team members use the full desktop installation of Word, rather than the browser version.
"Glad it wasn't just me and there is a potential solution for it. I have lost count of how many times I have become annoyed at having reformat documents as a result of this issue." – Proposal Manager
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