@egamma What problem did you say you had with shift+f4? It works as expected for me.
@roblourens my problem was that 'F4' gives focus to the editor and I could not press it repeatedly. I've tried to reproduce it with all extensions disabled and it worked well. Sorry about the false issue.
@roblourens the culprit is the C++ extension and the SwitchHeaders command (see below).
This means the users of the C++ extensions will have the same issue.
Given that the C++ extension is popular we should "fix this" by announcing this as a "breaking" key binding change in the release notes.
Shouldn't this be moved to C++ extension and the extension change its key mapping?
Add note about F4 keybinding conflicts to fix Microsoft/vscode#18679
Filed an issue on vscode-cpptools, and added to the release notes