Let Older Add-Ons Work With Firefox 3.0

mask.of.sanity informs us of a hack that allows old add-ons to work with Firefox 3.0. Short form: in about:config, create a new boolean and set extensions.checkCompatibility to false. "The fix, which requires a little boolean creativity, great for anyone not afraid of taking risks. The idea is to stop Firefox checking its version history, allowing defunct extensions to work... [Those who do] get the fix working will have to remove the code from the prefs.js file once the stable Firefox comes out, but will enjoy their [favorite extensions] in the meantime."

Comments

Do not do this

[amake]

Not only is this not news, but it's a bad idea. Straight from the horse's mouth:

You can not make your extensions compatible by changing a Firefox preference. So don't do it unless you're fully prepared to deal with major breakage!

Re:Do not do this

[DuncanE]

While it may cause breakage its a great way for users of the beta and RC version of Firefox 3 to get some fairly major extensions work.

I need IEtab to get certain work pages to work and I really love stumbleupon... So when Firefox 3 upgraded automatically to RC1 and these broke it was quite annoying so i disabled the check.

An example of an extension this wont fix is Google Browser Sync. You will need to disable this in Firefox 3 otherwise you WILL see some major breakage if you disable the check.

Re:Do not do this

[BZ]

I would fully expect IETab to crash, in general, unless you're using it with the exact version of Gecko it was compiled against (or one completely binary-compatible with it, like the security releases are).

Re:Do not do this

[Myen]

If I remember correctly, one of the top crashes for Firefox 3 betas was... people whole force-enabled Google Toolbar.

Yes, top crash.

This preference is generally not useful unless you know how to deal with the fallout (including figuring out what problems are due to extensions and which ones are not, and possibly fixing things locally).

Re:Do not do this

[__aabvlw4075]

This isn't about making extensions compatible, it's about forcing Firefox to allow you to use extensions that claim not to be compatible, but very well might be. Major breakage certainly could occur, but I find it worth the risk. Many extensions that I was using with beta5 claimed not to work in rc1. Forcing them to load anyway has been very helpful, and they have all worked perfectly without causing any problems (as far as I can tell).

Re:Do not do this

[Keeper Of Keys]

I did this; basically don't want to live without Google Toolbar. But the current version makes FF3 unstartable. I had to manually rip it out my extensions folder.

In any case, there' no need to hacking around in about:config; just use the Nightly Tester Toolds.

Re:Do not do this

[GigaplexNZ]

Odd, IE Tab is working fine here on FF 3 RC 1 without any modifications. That said, I find a safer way to get your favourite extensions working is to edit the version number in install.rdf which is inside the .xpi file (xpi is just a renamed zip file). That way when the extension updates normally, the hack doesn't stick around ready to break something later.

Re:Do not do this

[DuncanE]

Yes IEtab and stumble are compatible NOW, but werent for several days...

If you know what you are doing then disable the compat check for a couple of days...

And yes I know you can edit the extensions directly, but either they are going to get upgraded (like stumble) or they arnt (like Better Gmail2).

Re:Do not do this

[ta bu shi da yu]

While it is fine to disable the compatibility checking, my concern is that if enough people disable it they might start expecting the Mozilla devs to actually implement workarounds to 2.0 compat problems in v3. That way leads to many, many problems. Just ask Microsoft.

Re:Do not do this

[nmg196]

Why? IETab doesn't use Gecko, it uses IE. That's the entire point of it.

Re:Do not do this

[The MAZZTer]

You DO realize safe-mode exists so you can uninstall and disable extensions without having them running, so they can't crash Firefox.

Re:Do not do this

[Myen]

It's a NPAPI plugin with XPCOM interfaces to expose it to the UI. That is, it's tied to both sets of APIs. Notice how the back button actually seems to work?

Re:Do not do this

[BZ]

It hooks into the binary parts of Gecko to actually show the content Trident renders.

Is this a good idea?

[BadAnalogyGuy]

If FF3 is being used before a v1 release, it ought to be used in order to find bugs so that the development team can fix them for the release version. By breaking a specific part of the product in order to install unsupported addons, users are adding unecessary unknowns to the equation and negating their contributions to the product test cycle.

I'd say hold off on FF3 until it is released if you can't live without your plugins.

Re:Is this a good idea?

[DigitalisAkujin]

Personally, I've been using the betas of Firefox 3 as main because I couldn't stand Firefox 2. This RC1 release is heaven. You guys think this release is buggy when really there's just a few bugs to fix and most of them on foreign versions or very specific cases equally in windows, linux, and mac based on the ratio of installs.

Re:Is this a good idea?

[bloodninja]

I'd say hold off on FF3 until it is released if you can't live without your plugins. While I planned on waiting until Firefox 3 is released before switching, I found it preinstalled in Ubuntu 8.04. So I'm using it. I do think that Ubuntu made a bad decision by including a beta web browser, I understand why they did that. The problem is not that the Firefox betas and RCs are buggy. The problem is that misuse of the term beta has led people to expect no less from a beta than from a full release. Gmail has been in beta for years, and it is [arguably] the most complete, feature-rich webmail available. How long was ethereal beta? 10 years? It was pretty stable for at least the past five years, at least, no less than any other full release software. Beta has become a marketing term for "new".

Re:Is this a good idea?

[Anonymous Coward]

In the same vein, shouldn't extension developers follow the Fx beta stages so that users will actually switch to 3.0 once it is released, instead of having to wait for months until their plugins have left beta stage?

I use about 10 plugins since Fx 1.0, and have yet to encounter a single crash due to an extension (the only plugins that crash my browser are GCJ and Flash). Disabling compatibility checking has been a blessing for me, because it means I can use the latest version of Firefox and still use all extension that I don't want to browse without.

(Before I knew of this option, I used to manually edit the extensions manifest file to fake compatibility with newer versions)

Re:Is this a good idea?

[Anonymous Coward]

Pray tell, what's a foreign version?

A bit less strict disabling rules, please

[Rah'Dick]

I always wondered why some extensions got disabled from one minor bugfix release to the next. Has the underlying API been changed so much, that the extension really isn't going to work anymore or is the extension's author just being a bit restrictive with the "max. version allowed" setting?

Re:A bit less strict disabling rules, please

[rubah]

Both. Things like forecast fox don't depend so much on the browser so long as they can sit happily in the statusbar (at least how I use it it's happy), but things like firebug get honest-to-gosh broken. As in you can open it and use it to edit css to show in a page, but it will not call the stylesheets or outline an element you hover over. So it's still kinda useful but heavily limited.

for a given of 'small bugfix' anyways.

Re:A bit less strict disabling rules, please

[Keeper Of Keys]

There is a beta (1.1) on the Firebug page which works just fine in FF3.

Re:A bit less strict disabling rules, please

[maxume]

There is a goal inside of Mozilla not to break extension compatibility for minor releases, and the documentation on their website suggests using maxVersion of the form 2.0.0.* for Firefox 2:

http://developer.mozilla.org/en/docs/Updating_extensions_for_Firefox_2#Step_1:_Update_the_install_manifest

For Firefox 3, they suggest moving to the form 3.0.*:

http://developer.mozilla.org/en/docs/Updating_extensions_for_Firefox_3#Step_1:_Update_the_install_manifest

So no, devs aren't breaking any rules when they mark their extension as being forward compatible.

What is this?

[Zouden]

What is this, the 'tips n tricks' column of a newspaper's IT section?

The fix, which requires a little boolean creativity, great for anyone not afraid of taking risks.

Not afraid of taking risks? It's about:config, not instructions for making a Linux-powered flamethrower, which I think would be a much better article for Slashdot.

Re:What is this?

[JavaBasedOS]

I'd advise against the Linux-powered flamethrower, as I almost melted my face off trying to recompile its kernel.

Re:What is this?

[Chrisq]

I'm sure I'll be safe with the Microsoft powered flame thrower.

Re:What is this?

[Hal_Porter]

Fire wants to be free.

Re:What is this?

[mk_is_here]

Ah yes, the Blue Flame of Death!

Re:What is this?

[Eighty7]

It would be their first cool product.

Backwards compatibility

[Lord Lode]

It's a loss if old plugins don't work, some plugins are nice but unmaintained. An example was PrefBar which also suddenly didn't work anymore in FireFox 2.0, until much later. It's a shame that no backwards compatibility is provided out of the box. Not saying I'm for the above idea though.

os dependency

[genican1]

I hope that soon they'll disable the creation of OS dependent add-ons. Man, I really want my browser to match aqua. so what if I don't have osx?

Takes a long time to filter

[IBBoard]

Obviously tips like this take a long time to filter through to Slashdot, for some reason. I saw that tip when first using Firefox 3 betas, and according to the Mozillazine knowledgebase it has been there since Firefox 2! It also covers an extra bit that the summary doesn't that might still stop extensions working in Firefox 3.

And after all that, I originally used the Nightly Tester Tools to check the compatibility of some extensions. Some of the simpler ones worked, but AdBlock Plus couldn't just have the FF2 version enabled (it wouldn't auto-fill the filter address, but they have an update) and neither could the Web Dev toolbar (the edit CSS tab wouldn't close, amongst other things). Both of them have now been updated for the RC.

I think this one is definitely tagged right - "!news". Now all it needs is "badidea".

Nightly Tester Tools

[DemonThing]

This addon lets you selectively override addons' compatibility, among other things.

This extension adds a few extras useful to those that regularly test nightly builds of Firefox, Thunderbird, Sunbird and Toolkit Seamonkey (Suiterunner).

The following is a brief list of the extension's features, for the full set of features please visit the extension home page.

• Extension compatibility fixing
• Titlebar customisation
• Build ID retrieval
• Screenshots
• Breakpad information
• Restoring tabs from previous session
• Leak log analysis

Re:No Foxmarks...

[Cyvros]

There's a beta version of Foxmarks for Firefox 3 that's now been opened.

Test the extentions one at a time

[fairyprincess]

Every extention has an install.rdf file which contains the version numbers it works with, if you go to your profie dir and then extentions you can move the extention folders out, edit the rdf files in notepad then restart firefox - it will have no extentions, close it, then move all the extention folders back one at a time restarting firefox everytime, that way you are only adding back extentions that you know work, but just haven't been updated by their developers to install. This can also be done by renaming the .xpi files to .zip then opening editing then returning to .xpi and installing. If you are comfortable doing this i view this as safer than just allowing all addons as if something was crashing firefox you would have no idea, where as if it did you would know and you would live without one extention rather than one.

This is really, really stupid

[Idaho]

Sure you can disable the mechanism that checks whether plugins are compatible.

However, as is to be expected with major version changes, lots of API's will likely have changed, so if the plugins happen not to crash outright, they might fail in subtle ways that you don't discover until it's much too late.

This is pretty much exactly why the mechanism is there in the first place.

So if you do this, don't complain about "bugs" regarding crashes, memory leaks and pretty much any other problems you may experience with Firefox. There likely will be a lot, if you go down this road.

Re:This is really, really stupid

[Waccoon]

Not to sound terribly dumb or inexperienced, but should we really expect extensions to cause crashes, memory leaks, and pretty much any other problem we might experience with Firefox?

Don't extensions run on some kind of VM or something? People yell at Windows for all of its stability problems, and practically everything in a modern web browser behaves like it's single-threaded?

We do live in 2008, right?

Re:This is really, really stupid

[Tim C]

practically everything in a modern web browser behaves like it's single-threaded?

Yes it does, hence the entire browser stalls when one tab is busy for some reason.

Re:This is really, really stupid

[Idaho]

Don't extensions run on some kind of VM or something? People yell at Windows for all of its stability problems, and practically everything in a modern web browser behaves like it's single-threaded?

I agree about the singlethreaded thing. Apart from that: no, extensions can't run in some kind of VM. If they did, they would not be able to modify the browser in interesting ways (as this in many cases needs r/w access to internal browser state; this would not be available if you run it in a "sandbox" or VM.

You can pretty much have the exact same argument about Linux kernel modules: the kernel refuses to load modules that are compiled for the wrong (=a different) kernel version. Now, you could say, modules should not be able to crash the kernel, right? Well...if you could limit the interface between kernel and modules in such a way that modules would probably run about 5x slower, needs twice the amount of code to write *and* be unable to do a lot of things that would be interesting because the strict interface does not allow this, then yes. If we don't want to make that sacrifice (and in fact we don't), the smarter way is to only allow modules to be loaded that are actually at least compiled against the correct kernel version.

We do live in 2008, right?

Last time I checked, yes. Your point being that software composition problems are just supposed to somehow magically solve themselves these days?

Speaking of hacking Beta Software...

[hyperz69]

Here is another boolean hack but for Vista! Just set that boolean variable

CRASH = TRUE
and
EATALLMYDAMNRESOURCESWITHDRM = TRUE

to FALSE

I wonder if I can set OMGIGOTAGIRLFRIEND = TRUE... THE POSIBILITIES!

Re:Speaking of hacking Beta Software...

[Rudisaurus]

I wonder if I can set OMGIGOTAGIRLFRIEND = TRUE... THE POSIBILITIES!

I tried that. It ate all my resources.

Google bar kills my FF3

[MadMidnightBomber]

You have been warned :)

Recovery is to delete the plugin, something like this:
egrep -ri google .mozilla | grep toolbar
.. ( see where it lives ) ..
rm -rf .mozilla/firefox/zy8uo2wh.default/extensions/\{3112ca9c-de6d-4884-a869-9855de68056c\}

Re:Google bar kills my FF3

[mstrom]

Recovery is to delete the plugin, something like this:

...

Ouch,manual removal of add-ons :(

Simpler way is to start Firefox in safe mode which has an option to disable all addons on startup, after which it can be uninstalled from within firefox safely.

firefox -safe-mode if my memory serves

How to test compatability before upgrading?

[egghat]

I'm on OS X and FF3 doesn't allow a parallel installation of two Firefoxes.

Is there a way to test all my installed extension in advance?

Sorry if this is a dumb question but I couldn't find anything with googling.

Finding out incompatibilities in advance?

[Pahalial]

On that note, is there any -easy- way to check addon compatibility before upgrading to FF3, i.e. other than looking each addon up again? As I understand it they all have a builtin version range, why can't I just go to my addon list and see the compatibility of each addon?

Re:Finding out incompatibilities in advance?

[jalefkowit]

Check the extension's listing on addons.mozilla.org. The site checks what version of FF you are using, so if you're browsing with FF3 and you look up an extension that hasn't been updated, it'll say "this add-on is for older versions of Firefox".

Disabled install button

[lofoforabr]

Well, I've been using this pref since the early days of Minefield. I find that most extensions I use work fine under Minefield. Here is a list of them:

• Adblock Plus
• del.icio.us
• Fasterfox
• Flashblock
• Greasemonkey
• Live PageRank
• NoScript
• Web Developer Toolbar

One thing to note, though.. I think recently the mozilla addons site has been changed, and the button to install is now disabled if you use a not-officially-compatible browser version.

To overcome this, I first install NoScript (it's compatible with Minefield), and then blacklist the mozilla addons site, so it will not run the javascript that disables the button (yes, it's javascript). Then I can install whatever I want.

Of course, I had a few problems with some extensions. Turned out they really were incompatible, but from my personal experience, most of them work just fine under Minefield.

Restoring compatability

[clownface]

> [Those who do] get the fix working will have
> to remove the code from the prefs.js file once
> the stable Firefox comes out

Not true. There is highly visible UI in the Firefox 3 AddOns Window which lets you to turn compatability checking on again.

Firefox Portable

[EnOne]

I would recommend Firefox Portable if you want to see if FF3rc1 is right for you. No registry changes and it allows you to add your extensions without issue. I have 10 add-ons that I use with Firefox and last time I tried to do a blind upgrade with forced add on use Firefox would not even start.

Location Bar

[Toonol]

I just installed Firefox 3.0 this week. I'm generally happy with it, but is there a fix for the horrible location bar auto-complete yet? My jaw dropped when I saw it pop up... what an ugly, ugly, feature. It seems like a pet change of the creators, too, so they don't have any option to turn it off in about:config.

Re:rickst29

[rickst29]

To be absolutely safe, back up your profile directory from OUTSIDE Firefox and 'turn on' only a few at a time. If it breaks so badly that Firefox won't even start, just restore the proofile directory from one of your "backup" copies. BTW, there's some out-of-date comments here, NTT does not force you to "make ALL compatible" at the same time anymore.