OneDrive long file path with FSLogix

Question

Platform: Windows 10 Pro 21H1 and 21H2, virtual machines

We are synching a SharePoint document library and it has some very long file paths. We also use FSLogix to store user profiles.

If we sync the SharePoint library inside the user profile, we are unable to open documents in particularly long paths.

But if we move the sync location out of the default user profile (for example we can sync to C:\temp), then we are able to open the files in the same long path.

We have already implemented a registry key that is supposed to enable long file paths in Windows, but this had no effect.

Has anyone encountered this before and found a fix?

https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=cmd

New-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\FileSystem" ` -Name "LongPathsEnabled" -Value 1 -PropertyType DWORD -Force