So I received an Message from an OneDrive for Business User:

Thank you for your exciting contribution. I find the feature very promising. However, I have difficulties when the files or the SPO library are not synchronized with OneDrive 4 Business.

The behavior is as follows: I open the file with „Open in App“. The PDF file is opened with Adobe Acrobat, for example. If I change something and save it, the new version is also online. So far so good…

But if a colleague changes the file and I open the file again:

I now get the version that is still in the OneDriveCloudTemp folder and not the current one from the SPO.

If I delete the file manually from the OneDriveCloudTemp folder and open it again, the current version is retrieved from SPO.

I send this question to Microsoft. And here is the Answer from the Microsoft Product Group:

We recently made an attempt to fix this issue. When a file is renamed on th web, if we already have an “Open in App” version of the file, we will make a call to make sure we’re up to date, or update if needed.

This should mitigate this case with one exception – if the user interacts with the file directly in the temp location. This temp location is meant to be an implementation detail and hidden from users, and any interaction with it directly is considered unsupported. The Sync client is meant to manage the lifetime of these files, and they don’t behave as other regular synced files. 

This fix is rolling in the OneDrive Version 24.070.0407.0001 and up.

Here you find my Original Post about „Open In App“