Reading time indicated on the Firebug Net tab

Question

See this screenshot from the Firebug Net tab:

http://www.scdi.org/~avernet/try/firefox-times.png

I know that:

• The time between 1 and 2 is the time it took for my application to generate HTML and to get the data into the browser.
• The time between 3 and 4 is the time spent on my JavaScript initialization code that runs on DOMContentLoaded.

But what about the time between 2 and 3? Is that what Firefox does to render the page? In this case, it is quite significant (about 1.5 seconds). How to optimize this part?

Answer 1

2-3 - , 1-2. HTML CSS javascript, . : 1) 2) , HTML/CSS 3) / CSS.

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