Recently, we covered how to start Mozilla Firefox in Safe mode. In the safe mode of Mozilla Firefox, addons and plugins will not be loaded, so it is very useful for troubleshooting issues with plugins and add-ons which affect the browser performance, stability or prevent it from being started. Mozilla developers decided to add an additional way to launch Firefox in safe mode.
The Developer edition of the Mozilla Firefox browser comes with a different, dark theme. I discovered a trick which will allow you to switch between dark and light themes for Firefox Nightly builds. After you follow the instructions in this article, you will be able to switch between the regular and dark theme via the Customize mode of Firefox.
I have three versions of the Firefox browser installed simultaneously, including Firefox stable branch, Nightly and a special UX build. I use Nightly for my regular browsing tasks very often. Yesterday, I noticed that the browser was preventing me from using the Google +1 service and Gmail as well and Google was showing me the following error message: Oops! your browser seems to have cookies disabled. Make sure cookies are enabled or try opening a new browser window. I had not changed any settings and cookies were enabled, however, the error still continued to occur. Here is how I fixed it.