It happens to be I need to edit a massive JavaScript file and I tried to speed through it, however, my instance of Visual Studio 2017 is not helpful by trying to be helpful.

Every single key stroke triggers a 1-5 seconds pause which sometimes caused a pop-up with "Please wait for an editor command to finish" message to show. Worse, that pop-up is not cancelable.

Additionally, my CPU usage was hovering at 80-90% just editing JavaScript! As of this time, my Visual Studio 2017 version is 15.9.25.

Seems like it is triggered by some auto-suggestion tools which in Visual Studio, Intellisense seems to be the culprit. I ended up going to Tools > Options > JavaScript/TypeScript > Formatting > General and uncheck everything under Automatic Formatting.

Even after that I still noticed a half-a-second delay on some keystrokes, so I also uncheck Tools > Options > JavaScript/TypeScript > Linting > General > Enable ESLint.

That made my life a whole lot easier. It also drops my CPU usage to 10-20%.