Start second Firefox with profile manager:
"C:\Programme\Mozilla Firefox\firefox.exe" -no-remote -ProfileManager
Old versions of firefox seem to need:
SET MOZ_NO_REMOTE=1 "C:\Programme\Mozilla Firefox\firefox.exe" -ProfileManager
browser.gesture.pince.in — Value = cmd_fullZoomReduce browser.gesture.pinch.in.shift — Value = cmd_fullZoomReset browser.gesture.pinch.latched — Value = false browser.gesture.pinch.out — Value = cmd_fullZoomEnlarge browser.gesture.pinch.out.shift — Value = cmd_fullZoomReset browser.gesture.pinch.threshold — Value = 40 to 100 (set it to a number that works for you)
This ist outdated on current versions of firefox, use extension Classic theme restorer instead
To put the tabs bar again down in recent versions of firefox without the respective menu item:
browser.urlbar.trimURLs = false
browser.fixup.alternate.enabled = false
I just encountered the (in)famous “The PKCS #12 operation failed for unknown reasons.” error message while trying to import a personal PKCS#12 certificate and key into firefox 43 or firefox 45 on ubuntu.
As the the import worked on a different firefox profile by the same user account on the same machine as expected, I concluded that the certificat file was okay, but I had some runtime or configuration issue within firefox.
While neither finding helpfull information on the web nor some means to do analytic troubleshooting, I just started to try out things.
In the end, it turned out that starting firefox without my previously opened tabs allowed me to import the certificate in question.
So some of my opened tabs did prevent installing a personal certificat into firefox … - WTF???
It my happen, that firefox replaces http by https when trying to reach a site. I susspect, this happens, when there has been a redirect to https before (or even you just used the site with https before). However, if http and http content do not mach - or even if there is a problem with the https site- you'd prefer to access the http URL. Alas, the following steps seem to work:
After some Update, checkboxes on webpages were not visible any more. Utilizing my favourite web search enging1) made me realize other people had the problem too. In my case (running XFCE under Ubuntu 16.04) the solution was to start XFCE-Theme-Manager2), select tab controls and switch from Orion to Murrina-Tangoesque.