Anyone else that have the problem when you click on a code link, after error, in the Console an additional Visual Studio session is opening and not the same as is open?
Not for me, but is your Unity Editor configured to open your cs files using "Open by File Extension" by chance? See step 3 in the below thread. https://forum.unity.com/threads/intellisense-not-working-with-visual-studio-fix.836599/
Try changing it to point to your VS executable then, per those instructions. See if that fixes the issue.
I get it consistently after I add a code file. The next VS switch opens a new instance. Same thing happens if there's a modal dialog open in VS. I am guessing that the instance doesn't respond to Unity, so Unity just opened a new one.
The only problem I get all the time and it's annoying - if I import any new script (E.G. An asset from package manager) it automatically opens up VS again. (not a new instance), just opening the same one up every time, any time I compile it opens it up, it's really obnoxious.
Possible fix was discussed in this Beta discussion thread – check for open VS dialogue boxes. That might prevent Unity from communicating with VS and so opens a new instance.
Yes - super annoying. Removing Visual Studio Editor and Visual Studio Code editor from the Package Manager fixed it for me. Hasn't caused any bad effects as far as I can tell.
This most often happens for me if I double-click on a script to open it while Unity is compiling. If I wait for compilation to finish first, it usually doesn't open a second VS instance.
May I ask, how you do that, when Unity normally gets locked from any other action, when compiling? For me most of the time Unity -> VS behaves ok. However, I had previously few occasions, where new VS instance get opened. Nothing that is obstructing atm. More annoying part is occasional reload of VS, when saving and compiling, causing reset of any stored undo actions in VS. But not sure, when that happens, or how to reproduce.