If you feel that you are working with mozilla firefox is very slow, you can make settings manually in a way like the following:

1. Type about: config in the address bar and press Enter
2. In the filter search bar type network.http.pipelining. check values and set true, if not double-click to set true.
3. Back to the filter search bar and type network.http.pipelining.maxrequests. Double-click and set value to 8.
4. Idi filter search bar and type network.http.proxy.pipelining. DoubleClick and set set true.
5. IN network.dns.disableIPv6 type filter search bar and set to true

6. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Boolean and will exit pop-up menu.
1. content.interrupt.parsing enter in the New boolean value pop-up window and clik ok.
2. and select the true value and clik OK.
7. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Integer and will exit pop-up menu.
1. content.max.tokenizing.time enter in the New integer value pop-up window and clik ok.
2. and enter the value 2250000 and clik OK.
8. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Integer and will exit pop-up menu.
1. content.notify.interval enter in the New integer value pop-up window and clik ok.
2. and 750,000 values and clik enter OK.
9. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Boolean and will exit pop-up menu.
1. content.notify.ontimer enter in the New boolean value pop-up window and clik ok.
2. and select the true value and clik OK.

10. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Integer and will exit pop-up menu.
1. content.notify.backoffcount enter in the New integer value pop-up window and clik ok.
2. and enter the value 5 and clik OK.
11. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Integer and will exit pop-up menu.
1. content.switch.threshold enter in the New integer value pop-up window and clik ok.
2. and 750,000 values and clik enter OK.
12. Click the right. (Apple ctrl-click) on the about: config window, select New trus select Integer and will exit pop-up menu.
1. nglayout.initialpaint.delay enter in the New integer value pop-up window and clik ok.
2. and enter the value 0 and clik OK.
13. Now, close firefox, and open it again and congratulations to enjoy browsing much faster than usual.