Not compatible with latest version Rated 1 out of 5 stars

Shame. Doesn´t work with version 31.5.0.

Yes you can use Red Cats Green or Blue in Firefox 34 Rated 5 out of 5 stars

You must have 7-zip, which is freeware. If you don't, find it on the web and download and install it. Go to your preferred color Red Cats download link in Firefox Add-ons page. Right-click on the link and click on save link. Save it to your folder choice on your computer. It will save as either a jar or xpi file. Right click on that file and find open archive in the items 7-zip has added to your right-click menu. Click on open archive. Scroll down to the install.rdf file. Right click on it and click edit. Open it in whatever text editor you use - Notepad is fine. Locate where it says min and max versions and change the max version from 32.0 to 34.0. When you click the "X" to close the file in the right-hand top corner it will ask if you want to save the file. Click yes. It will then ask if you want to update the file. Click yes. Now open Firefox add-ons page and click on the gear that allows you to install an add-on from a file. Browse to that file you just updated and click on it. It will install and you will need to restart Firefox and when you do you will have your Red Cats back.

Missing the Cats Rated 5 out of 5 stars

I really miss my Red Cats theme and the update seems to be taking longer than usual. Today I read an article about changes coming to FF that made me wonder if I'd ever see my cats again:

So, why update now when changes are expected? But please, Red Cats creator, please continue with your theme, even after the changes are in effect. Red Cats may be the only reason I'll use FireFox because normally I avoid Yayhoo as a potential link to malware. Here's part of a comment quote from the above link re Yayhoo: "I mention all this, because I have noticed a distinct correlation between Yahoo users and their PCs being rendered practically unusable by malware - so this news worries me as a Firefox user."

I hope Mozilla addresses the changes with it's loyal followers.

This user has 2 previous reviews of this add-on.

5.7.0 problems on Pale Moon version 25.0 Rated 4 out of 5 stars

Pale Moon was officially updated to version 25 on Oct 10. 5.6.3 version passed updates check (but that's because Pale Moon has not yet forked all themes and doesn't mean it is fully compatible) on my internal updating on Windows 8.0 Pro and Windows 10 Preview and works ok on both computers, but I decided to again try 5.7.0. That version appears to install correctly BUT the Menu bar was MISSING. "Customize" showed the Menu bar was checked and should be showing but was not and I could not see any way to retrieve it from where ever Red Cats stashed it. So, I had to revert Pale Moon 25 to Red Cats 5.6.3 version for the time being. (Pale Moon plans to fork ALL themes and fix them/invite developers to fix them so until they do that, I can use this earlier version). If anyone knows of a way to fix the Menu bar problem using 5.7.0 on Pale Moon 25 please post it. Pale Moon 25 has major changes and further distances itself from Firefox so I am not particularly surprised that 5.7.0 doesn't work right on it.

JoeG is a using a nightly. All bets are off on a nightly so his comments are not particularly relevant to the release versions of Fx 24 ESR where 5.7.0 causes a huge mess. JoeG says that changing "browser.preferences.inContent" from "true" to "false" fixed his problems with 5.7.0. That's confusing because "FALSE" is default (so I wonder why how he managed to have it set to "true" since he had to have someone else tell him about the preference). With that preference defaulted to "false", I had a horrible mess with 5.7.0 on Fx 24.6 ESR and since then on Fx24.8 ESR (which is the final version and which will be automatically internally upgraded to Fx 31 ESR in early November). I'm sure 5.7.0 will work on it because 5.7.0 is written for Australis which is why it doesn't work on Fx 24x ESR.

I would love to see Red Cats developer work with Pale Moon to create a Red Cats that is FULLY compatible with Pale Moon 25 (as 5.6.3 works but Pale Moon says it is not truly compatible). Pale Moon will be contacting theme developers about this issue which is the case for all Fx full themes. Pale Moon now has its own repository for extensions and themes. Full themes like this one are going to take center stage at Pale Moon which I think is great so I'd like to see the developer join their efforts.

This user has a previous review of this add-on.

Rated 5 out of 5 stars

Nice color, graceful cat on icons, comfortable and friendly environment — all that is needed for happiness!

5.7.0 fine with ESR 24.6.0 Nightly / Solved problem with Options Rated 5 out of 5 stars

This has been, is, and always will my favorite Fx theme. My sincere thanks to the dev for what was certainly a Herculean task in getting it to work with the interface whose name we do not mention. :-0

Contrary to what the previous reviewer reported, v. 5.7.0 has not caused any problems whatsoever for me on the ESP 24.6.0esrpre Nightly (Yes, I know 24.6.0 has been released), which I've been using for about five months. It works without a hitch two of my Win 7x64 machines and on three older XP machines.

In fact the only problem I had was with v. 33 Nightly - with the hated Aus .... interface.

The problem was that "Tools-Options" opens in a tab rather than a pop-up window, and this part of the interface was broken.

I saw the nice vertical row of red cats along the left, but nothing could be clicked. The only way to use Options was to temporarily disable Red Cats.

Fortunately, one of the kind contributors to the Fx Forums told me to me to change the pref "browser.preferences.inContent" to false. This was the solution!

Now everything's fine.

This user has 2 previous reviews of this add-on.

Rated 5 out of 5 stars

I have used and loved Red Cats for years. But it's just not working with Firefox 28 - no matter whose advice I try and follow (thanks to everyone who has offered help in the past!)

Why did Mozilla think this was a good idea?

This review is for a previous version of the add-on (5.6.3).  This user has a previous review of this add-on.

Beta for FF 27 Rated 5 out of 5 stars

The cats are back - looking and working as they always. I received a beta copy and have had not problems yet. :)

This review is for a previous version of the add-on (5.6.2).  This user has a previous review of this add-on.

Rated 5 out of 5 stars

Потрясающая тема, мягкие и приятные для глаз (моих) сочетания цветов!
Забавный индикатор прогресса в виде рыбок!
Теперь это моя любимая тема (раньше walnut использовал), она более "весёлая"! ^_^
Жаль, что автор "пряничную" тему Curacao не развивает... T_T

This review is for a previous version of the add-on (5.6.2). 

Yay, the red cats are back! Rated 5 out of 5 stars

Red Cats Green Flavor has always been my favorite Firefox theme (& I love its Blue Flavor cousin too)! My lazy tuxedo & lazy tabby cats love it too.

Now works with Firefox 24, & looks like it's good to go for the next couple of upgrades too — "Full compatibility with Firefox 27.0a1." I realized I'd been using this great theme for years without ever fully showing my thanks, so I just thanks to the developer Red_Fat_Lazy_Cat by sending a Paypal donation. Thanks Red Cat!

This review is for a previous version of the add-on (5.6.2). 

The Best!! Rated 5 out of 5 stars

Red Cats (green flavor) is the only thing that keeps me using Firefox (not lying), please fix it...

This review is for a previous version of the add-on (5.6.1). 

Fixing Red Cats after FF upgrade Rated 5 out of 5 stars


A year ago DaveShep posted an incredibly useful fix for when Firefox upgrades and Red Cats stops working:

1. Download Red Cats (Green Flavor) using IE or Chrome
2. Change the extension of the file from .jar to .zip.
3. Open the zip file & copy the install.rdf file out of it.
4. Open the install.rdf file w/ Notepad
5. Look for the line that begins "<em:maxVersion>"
6. Change the version number to 14.* (this will allow it to work w/ all versions of FF 14)
7. Close & save the file
8. Put it back in the zip file.
9. Change the extension back to .jar
10. Go into Firefox's AddOn Manager & install Red Cats (Green Flavor) from file.

My grateful thanks to him for this; I used it every few weeks when FF screwed up Red Cats (amongst other add-ons; their constant upgrade policy really is stupid, because it ruins what used to be the great beauty of FF, its many useful add-ons).

With the upgrade from FF22 to FF23 I've lost Red Cats again, and this time can't get this fix to work.

A query to the developer. Would it be possible for you to set the maxVersion to 99? -- then we wouldn't have this problem every few weeks.


This review is for a previous version of the add-on (5.6.1).  This user has 3 previous reviews of this add-on.

Very pleasant theme for eyes. Rated 5 out of 5 stars

Some years later again I installed it.

This review is for a previous version of the add-on (5.6.1).  This user has a previous review of this add-on.

Rated 5 out of 5 stars

I love this addon, but i lost it cuz mozilla updated itself to 23.0. it was actually still working for a bit after update, but stopped. I do hope you can update it.

This review is for a previous version of the add-on (5.6.1). 

Rated 5 out of 5 stars

Thanks very much I have soooo missed my red cats green flavour - it is just how my browser should look to me :) Now my Firefox is back to how I like it - Thank you again
PS: Putting it on PCs at work tomorrow!!

This review is for a previous version of the add-on (5.6.1). 

Thank you & thank you again! Rated 5 out of 5 stars

OK, as advertized, one can never have too many cats. Thank you for updating this wonderful theme.

Oh yeah, the icons are much easier to read & to the point than the default's icons. Been using them for years.

This review is for a previous version of the add-on (5.6.1).  This user has 4 previous reviews of this add-on.

Rated 5 out of 5 stars

Самая любимая моя тема, и не работает под ФАЕРФОКС 19 !!!!!! Сделайте же что - нибудь!!! ((( После обновления браузера всё слетело.

This review is for a previous version of the add-on ( 

Latest beta Rated 1 out of 5 stars

Themes for FF are based on Java - and yes, Java is able to corrupt your browser. Yes, I may have run into some FF bug – now, could you possibly allow for the fact that your beta had a flaw in it which clashed with the latest FF or its latest bug? And, as a developer, could you please see what you could do about it instead of categorically saying such data loss has nothing to do with your buggy theme? This is why I am writing here, this is the sole reason.

Why am I blaming this beta? Because prior to installing it everything in my FF was working OK! How come it corrupted my bookmarks when you say that is impossible? Well, there is always a FIRST, isn't it?

Why did I uninstall and reinstall FF? Because I desperately wanted FF to function with my favourite FF theme ever and often this is what computer manuals tell you to do when things do not work as they should – do your backup, uninstall, reinstall. I am very sad to let this theme go, but I was inifinitely sadder to see all my bookmarks vanish :(

This review is for a previous version of the add-on (5.5.2).  This user has 3 previous reviews of this add-on.

RE: Latest beta

You disabled the Red Cats theme and everything was OK again. Your bookmarks were NOT lost - it clearly proved that the theme did nothing to them. The next logical step would be to uninstall the theme and/or contact the developer and ask him/her for help. But you desperately wanted Firefox to function with your favorite theme so YOU ATTEMPTED TO FIX THE PROBLEM ON YOUR OWN by uninstalling/reinstalling Firefox and deleting files. Sorry but you only have yourself to blame. I fail to see how it's related to any add-on.

And yes, as a developer, I can categorically say it's impossible for a theme to corrupt any data in your profile. Unlike you, I know it. Feel free to post on MozillaZine or Firefox Support if you don't believe me.

And no, as a developer, I can't do anything about it. I have no control over your actions and hence I cannot prevent you from doing something you're not supposed to.

And no, Firefox themes are not based on Java. They're nothing but a bunch of images and CSS files. Please learn to do some research before jumping to conclusions.

And for the umpteen time: accusing beta of being buggy is like accusing water of being wet. Please do me a favor and familiarize yourself with the definition of "beta" on Wikipedia or somewhere else.

If you still have any questions to ask of me, contact me by email or use the support forum.

Rated 5 out of 5 stars

thank you for giving me my kitties back!!! way to go beta version. I tried everything to get my cats back to no avail...then out of frustration I re downloaded it even though it says it is not compatible with my version of firefox, when low and behold I happen to read the description and there is a link and instruction to the beta version yay!! this made my night and made my pc mine again!....Thank you...

This review is for a previous version of the add-on (5.5.2). 

Firefox 15 Rated 5 out of 5 stars

I just redid the jar file, setting the version number to 99. Works that way for FF 15. We shall see if FF manages to break it in the future.

This review is for a previous version of the add-on (5.5.2).  This user has a previous review of this add-on.