Startup overhead

Reduced startup overhead of Preferences search cache when it's already up to date.

Is this what was preventing Drive C from showing in the tree for around 1 minute?

Has been very obvious for at least ver 13

No, the caching during startup was only introduced in the beta before this one.

Does the C drive show up in File Explorer and everywhere else but not in Opus, or is the problem system-wide?

What happens if you navigate to C: (or a folder below it) in Opus when it's not showing in the tree?

How do you have the tree configured? (Preferences / Folder Tree / Expand/Collapse)

I will probably have to try that tomorrow when I have the problem to see how explorer works
I have a C drive button on my toolbar that seems to work easily enough, which has allowed me to bypass the problem until it shows in the the tree

Explorer shows drive C and works fine, while it's not showing in the drive tree on DOPIS

What happens if you navigate to C: (or a folder below it) in Opus when it's not showing in the tree?