Multiple Profiles in Firefox

Firefox has a neat built in feature that allows you to have multiple profiles in one computer. It can serve many different purposes, for example, if you share one computer with multiple people, each person can have their own profile. If you're a parent and want to maintain some basic controls on your children's internet experience, you could have a profile for them with certain restrictions applied. Profiles can be protected with a profile master password.

The feature of multiple profiles in Firefox comes in very handy when you're trying to debug issues and you think something interacting with the browser may be part of the problem; cookies, JavaScript settings, addons or the cache. Profiles are also great because you can save different settings one each one. You can save settings, bookmarks and user/password combination to help you streamline your blogging experience for example.

Often, when you're developing a theme, or any kind of code for the web actually, you might need a special set of tools to help along with the process. In Firefox, many of these tools come in the forms of addons. Addons are great, but maybe you don't need them all loaded each time just to browse the internet. You can create a profile named WebDevelopment for instance, which will have addons specifically geared towards web development, while keeping your regular profile separate and focused on your browsing experience.

So what is a profile? A profile is a group of files that tells Firefox how to behave, and its represented in your computer by a folder which contains all these files. Normally when you start Firefox, it just uses the default built-in profile, you need to run a special command to get Firefox to show you the Profile Manager and allow you to create a new profile.

Here are some examples to illustrate:

• User Experience Testing. When you're testing websites, you need to make sure that the website is going to work as expected on the user's browser. It is important to anticipate any problems a visitor may run into, as well as unexpected results because of an addon. I don't think its enough to validate a website's code and call it a day. What happens if your visitor has a censorship addon, that blocks a section of your website? What happens if there's an auto-linking addon you didn't expect? Ideally you should have a profile with no addons loaded so you can see how your page will be displayed in a plain vanilla installation of Firefox. Second to the bare bones profile, I would recommend a profile with the top 3-10 addons as listed by Mozilla, it is likely that a large number of your visitors that use Firefox will have the same addons installed.
• Functional Work. Documentation, Quality Assurance, Research and other areas may benefit from very specific settings and tools that you don't need all the time.
• Troubleshooting. If your visitor complains about a problem and you can't figure it out, it could be an addon on his client. Activate a profile with the addon in question and test. Many times you'll be doing troubleshooting for yourself to make sure things look good and are working properly.
• Multiple Website Management. This is useful if you blog for many sites and you have a focused block of time you spend on each one, it is a bit inconvenient to keep stopping and starting Firefox to switch profiles but it can really be handy if you get into a process flow. You could have a profile setup for each website you manage, then customize the bookmarks toolbar to include shortcuts to the website's important admin pages. The bookmarks toolbar could also have links to promotional bookmarlets to sites like technorati. Profiles to manage multiple websites can also benefit from having username and password combinations setup for online services, like feedburner, twitter, stats and others.

Configure Firefox with another profile, and I always tell the Profile Manager to ask which profile it should use each time. Read more about profiles, and to get started see the instructions on how to use the Profile Manager, they're very simple but they're different for Windows, Mac and Linux so you should check out the document, it'll take you about a minute to do it. Good luck and let me know how it goes.