B3: vs +new .... What behavior should we expect now?

[jporkkahtc]

its much better than V17 now - doesn't complain about locked state file :-)
This:
    vs +new
    vs File.c
now works too (single instance of vs).

But, I'm curious - what was changed?
What should we expect it to do?

[Jerm_jp]

I am happy to see the +new issue resolved, but under the hood what has changed and how will the impact the configuration changes within each session's instance? Are there implementation issues that we should be aware of before 'using / abusing' this?