VS Code : how do I disable copy on selection

Go to File > Preferences > Settings and search for "Right Click Behaviour". Change the option of Terminal > Integrated: Right Click Behaviour from copyPaste to 'default`.

Settings: Editor: Selection Clipboard - uncheck

Happened to me while using VNC Viewer - The solution was disabling "Send primary selection to viewers" in VNC config window.

In the Files/Preferences/Settings search for "Editor: Copy With Syntax Highlighting" and disable it. That worked in my case with VS Code 1.42