Contents cache demo

Issue: 2356

Error in next_tick.js:228 process._tickDomainCallback

when I run npm run dev, the error occured

TypeError: Cannot read property 'data' of undefined
  
  - server-bundle.js:5564 
    server-bundle.js:5564:158
  
  - next_tick.js:228 process._tickDomainCallback
    internal/process/next_tick.js:228:7

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