In a DO lister with several tabs opened, when at least two of them are showing WevDAV servers contents (\ipAddress@port...), tabs content is sometimes messed between the tabs. For example:
Tab A: A local folder (i.e. C:)
Tab B: A WebDAV Server (i.e. \192.168.1.5@8080\somefolder)
Tab C: Another WebDAV Server (i.e. \192.168.1.6@8081\somefolder)
When navigating in folders on Tab C, Tab B suddenly changes to show contents from Tab C. Or Tab B ends showing files in local folder C:.
I'm sorry, but I'm not have been able to reproduce a defined behaviour pattern to demonstrate the issue. Seems a random thing, as if a pointer to the target tab for an operation like refresh/reload would sometimes wrongly assigned.
Opus has no concept of what WebDAV is and treats it as a virtual folder which is delegated to Explorer, so my guess (just a guess) is that you've found either a general problem with tabs (not just WebDAV ones) in Opus (which must be very hard to trigger as tabs get used a lot and there aren't lots of other reports), or a problem in the Windows WebDAV handler.
(Or you've done something like accidentally re-label one of the tabs to the name of a path it was showing, then changed to another path while the label remained, which was actually quite easy to do until a recent update.)
Your statement about no WevDAV relevance in the problem seems very reasonable.
I'd say that sometimes I've seen this confusion on regular/virtualised folders, with no WebDAV tabs implied, but as I'm not sure I'd preferred not to mention it. But with WebDAV folders issue is relatively frequent. Perhaps virtual folders delegation is having some implication in this issue.