Version !6, I can't believe this is still a issue, I see this problem was reported in V1.0
If you can't update the plugins then the whole browser is useless. .
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hello, you'll probably have to configure noscript correctly for the site to work (allow mozilla.org & mozilla.com), see https://support.mozilla.org/questions/755849
in case you cannot resolve it that way, launch firefox in safemode once & see if it's working there in order to rule out the influence of any extensions.
Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems
you might also want to install the search reset addon, since from the confoiguration you've provided it's apparent that the search from the address bar got changed by adware: https://addons.mozilla.org/firefox/addon/searchreset/
You can also try to reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.