Make sure you are not blocking content.

Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop

I started Firefox in Safe mode and loaded several different web sites. They all loaded but took from 5 to 10+ seconds to display. Also, the home page on several sites took up to a minute or more to stop loading.

Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

I think I found my problem. I checked all of my settings in Options again and noticed that "Enable DNS over HTTPS", which should have been on by default when I updated to version 74, was not checked. I checked it and now all the web [pages load quickly (less than approx. 1-2 seconds). I am not sure how this got turned off but it might have been turned off by a third party program when I tried an option to "increase internet speed" (far from it!).

That was very good work. Well Done. Please flag your last post as Solved Problem as this can help others with similar problems.

I'm going to load bookmarked pages and other websites in the course of a morning of normal use just to make sure that checking "Enable DNS over HTTPS" consistently works. If there are no more issues with "server not found" or slow/continually loading pages than I'll mark this as solved.

yes i get this problem too,, so resolve this issues i clear cache and history and update the browser jasa seo murah