That example works fine for me. Switches between red (off) and blue (on).
Using Vivaldi (Chromium based) latest build.
13 May 16:36:39 - [info] Node-RED version: v0.20.5
13 May 16:36:39 - [info] Node.js version: v10.15.3
13 May 16:36:39 - [info] Windows_NT 10.0.17763 x64 LE