Normally web page is being displayed, first we just click the request of link, when a link is clicked the page and its resources are downloaded. The document is the webpage file, which is just a text file. It is located on a web server. This file is often of the type ".html", but the type of file it is doesn't really matter. The important thing is that a text file is requested by the web browser. The web browser what ever you use the page resources to build the page and finally the web page is display.There are a four steps are often performed several times during a page load.

   1 Request
   2 Response
   3 Build
   4 Render

Hi wethands04, browsers and site authors use a number of strategies to try to avoid the "FOUC" (flash of unstyled content) but it sounds as though something is going wrong on your Firefox.

Could you test in Firefox's Safe Mode? In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, any userChrome.css/userContent.css files, and some other advanced features to help you assess whether these are causing the problem.

You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" Help button > Restart with Add-ons Disabled
• (menu bar) Help menu > Restart with Add-ons Disabled

and OK the restart.

A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement?

It is possible that CSS files come in slowly for some reason.

You can try to disable IPv6 (check for other possible causes as well).

• https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

Try the Firefox version from the official Mozilla server if you currently use a version from the repositories of your Linux distribution.

• https://www.mozilla.org/en-US/firefox/all/