Node.js App : white flash on page load

I have a very simple Node.js (express) app.

The pages are very simple, so fancy html, no iframes. I use jade to render them. Yet when navigating from one page to another, or simply reloading the page, a white screen / flash appears for a brief moment before displaying the actual page.

A similar question states that this behavior is normal, which is hard to believe given that none of my other websites behave like that, nor do much heavier pages. Ex : facebook, youtube, google, wikipedia ... do not have a flashy transition when navigating between pages.

My website is pretty light :

  • Page load time : 99ms
  • Page size : 34.4kB

http://tools.pingdom.com/fpt/#!/bjTSbm/http://165.225.137.117

Details : I have my app running locally as well as on a vps.

For the local version : The white flash appears on following browsers :

  • Chrome (MAC) 28.0.1500.71

But not on :

  • Firefox (MAC) 16.0.1
  • Safari (MAC) 6.0

For the vps version : The white flash appears on following browsers :

  • Chrome (MAC) 28.0.1500.71
  • Safari (MAC) 6.0

But not on :

  • Firefox (MAC) 16.0.1

What is the cause of this white flash and how can I solve that ?

Thanks a lot!