Make sure of the following:
You are using VSCode, Atom or an IDE that supports the Typescript language server
If you have created your own configuration file, make sure you restart after changing it
The typing documentation might not be active. There should be a little (i) symbol at the right of the intellisense, click it
The language server might not have picked up the changes, restart the language server/extension host
If you are using Typescript, the baseUrl property in the config file should be set
This is the type documentation. It should be part of your repo so that your IDE is intelligent about picking up the documentation.
semanticHighlighting on by default, which breaks several themes. Search this in your settings and turn it off. Hopefully this will be fixed shortly.