Update: 15:07 – Added Tab Mix Plus and TBE to the “not install” list.
ComputerWorld managed to generate quite a lot of buzz with its list of must-have extensions and extensions to avoid. But, as many commenters noticed, the extensions listed appear pretty random. The first list contains a number of extensions that are based on good ideas but either didn’t manage to implement these ideas properly or are simply useless to most Firefox users. On the other hand, some extensions that these users would really consider absolute “must-have” like Adblock Plus are simply missing which undermines the credibility of this article. The second article is no better. It lists several very popular extensions without giving good reasons why these should be avoided. And it is filled up with extensions that fall into the category “useless” — as if there were a point in warning users about hundreds of existing useless extensions. No wonder I have yet to see a single positive feedback on this article.
But since extension lists are so popular, I want to present here a list of my own. I do not expect anybody to agree with my choice of extensions, quite the opposite. That’s why I will describe each of them and tell who the extension is meant for, how good it is at doing its job and what its shortcomings are. Being an extension developer myself I choose extensions very carefully and evaluate them not only on the aspect of what they are doing but also on how they are doing it, something that most people don’t notice.
These are the extensions that I have been using for a long time and found very useful (in alphabetical order).
- Adblock Plus — surfing the web with all the ads is just too painful. The big advantage of Adblock Plus is that it doesn’t touch HTML code of the web pages and only blocks actual requests so that it is far less likely to break web sites than most other ad blockers. The extension attempts to appeal to users with very different skills. Newbies will simply select a subscription and forget about ads. Slightly more advanced users learn to use the context menu to block annoyances. Really advanced users use the list of blockable items and create good filters even for less obvious cases. And unfortunately it takes a really advanced user way too often because the ways in which ads are inserted into web pages get more and more complicated. The other problem of Adblock Plus is its user interface which could be more intuitive.
- ChatZilla — if you use IRC regularly you will want to install it. The user interface is very intuitive and comfortable while still having every feature you can ask for. Unfortunately, it started showing signs of bloat like overly complicated preferences dialog and nested context menus. ChatZilla could use some focus instead of trying to please everybody.
- Correct Identity — Thunderbird extension for people who dump all their mail into one account but still want to reply from the address that the mail was sent to. Thanks to that extension I could consolidate half a dozen mail addresses I use while still being able to sort the incoming mail — a great feature, especially given that this extension always works in background, completely unseen.
- Live HTTP Headers — shows HTTP headers for all requests sent out by the browser and responses received from the servers. It adds a tab to the Page Info dialog, the actual Live HTTP Headers dialog shows you far more information however and even allows “replaying” certain requests with some changes. Very useful tool for web developers and web security testers, especially since it intercepts SSL connections as well. Yours truly made sure that the most obvious shortcomings were fixed, no objections left other than some minor bugs.
- View Cookies — adds a tab to the Page Info dialog showing the cookies set for the particular page. This is especially useful for web developers and privacy fanatics. Very focused extension, it does only this one thing and it does it very good.
I am using a few more extensions that are useful but have considerable shortcomings.
- Adblock Plus: Element Hiding Helper — makes it easier to hide (not block) parts of web pages with Adblock Plus. Unlike Adblock Plus itself, this extension is primarily targeted at advanced users. The most critical issue is that you can easily create a rule that will hide far more than what you selected. This means that to use this extension properly you have to understand how it works which requires at least some basic HTML knowledge and ideally also CSS. But once you got over that hurdle it can be very useful.
- Dictionary Switcher — good for people who write texts in more than one language. While the spell checker is the killer feature in Firefox 2.0, it works based on the assumption that you mostly use one language. Dictionary Switcher is a big help here, and I exchanged a few mails with its author to improve it. Unfortunately, it still sometimes fails to switch the language correctly. Also, it often switches dictionaries unnecessarily. German dictionary is huge and takes a while to load which makes those unnecessary switches pretty annoying. Ideally the spell checker should be made to keep the dictionary in memory once it was loaded regardless of dictionary switching, I am not sure whether this can be done from an extension however. Still, Dictionary Switcher is certainly better than nothing.
- Stylish — lets you create and organize user stylesheets that will be applied to web pages allowing to change their look. Clearly targets advanced users even though there is a collection of pre-made styles. But the main problem is its rather awkward user interface, something that shouldn’t be hard to improve — and then Stylish would become a top-notch extension. Myself, I never add any permanent styles to Stylish since all the changes I need can be done with Adblock Plus already. It is useful to test things out however, like how Adblock Plus would look with a different icon.
Extensions I would never install
There are a few popular extensions that are often recommend and that I often install in my test profile for that reason. I would never use them in my work profile however.
- Adblock Filterset.G Updater — still often recommended “to update filters for Adblock Plus automatically”. Too many people don’t know that Adblock Plus is perfectly capable of updating filters itself and have to deal with the issues of Filterset.G.
- Fasterfox — is supposed to make your browser faster. My tests indicate in fact that this extension is not a placebo as I originally assumed, and that you get a ca. 20% improvement in page loading times. The price is high however. For a marginal performance improvement you significantly increase the load on the web sites you are visiting. By default Fasterfox will increase allowed number of simultaneous connections from 2 to 8. I know at least two servers that started banning users with too many simultaneous connections because of server load issues, and users who complained usually had Fasterfox installed. Also, Fasterfox enables HTTP Pipelining which is known to have issues with some web servers — yet my tests indicate that pipelining doesn’t have any notable effect on performance. Altogether, most hidden preferences that Fasterfox allows you to change are hidden for a good reason.
- IE Tab — the idea that you cannot use Firefox as your only browser and that there are many incompatible sites is very persistent. Maybe this is even true for some countries, but ever since Windows can be updated without going to Windows Update page I haven’t seen a single site that would not work with Firefox. If a site looks broken then maybe it is broken — tell the webmaster and come again in a week. Switching to IE for a site that looks broken is not just bad for web standards, it is also dangerous given all the known security holes in Internet Explorer. I use Internet Explorer for testing of course but I only point it to web pages where I know what they do. Finally, some time ago it was possible for a web page to force IE Tab to switch into IE mode. I analyzed the current version of IE Tab and could not find any similar vulnerability, but I cannot be sure that I didn’t miss anything.
- NoScript — advertised as a security solution. As I discussed earlier this extension doesn’t really make you any safer. People occasionally bring up the argument that they use NoScript and didn’t have a single malware infestation — but they should thank Mozilla developers, NoScript had nothing to do with it. People who simply kept their Firefox browser updated, even those who know almost nothing about computers and simply accepted the automatic updates, have made exactly the same experience. But since NoScript has a blacklist mode as well, it can be used as an annoyance blocker, and some people use it as such. Still nothing for me however, Adblock Plus blocks most annoyances already and the rest of them isn’t worse that NoScript’s attention-grabbing messages.
- Tab Mix Plus and Tabbrowser Extensions — are supposed to give you more flexibility with tabs in Firefox. This means first of all a preferences dialog that has far more options than Firefox itself. There are people who like this kind of bloat. However, the worst thing about it is the way how Tab Mix Plus and Tabbrowser Extensions are implemented. They rewrite browser functionality freely in ways that make the phrase “huge hack” an understatement. Result are obscure bugs that are difficult to trace back to the extension and are interpreted as Firefox bugs way too often. As a matter of fact, I add this to the list because I just looked into an issue some user reported: links opening pop-up windows (useful ones) didn’t work, the pop-ups were closed immediately without an obvious reason. At least, they were closed most of the time, one out of 5-7 pop-ups stayed.
I hope my perspective will be useful for some people. It is a short list, unfortunately good ideas only rarely meet good programming and user interface design skills so that I have to be very selective with what I install.