For all users Rated 4 out of 5 stars

Small tip: Because this addon lacks proper documentation, here a power user tip: press F9 to activate the replace-toolbar :)

Seems to be working but ... Rated 2 out of 5 stars

I hoped to find something like privoxy as addon but it is not working the same way. Foxreplace seems to changing source of web page (at least view source shows changes) but the changes are made to late. So all scripts are already loaded.

Works great with some minor issues Rated 4 out of 5 stars

The issue is with addon installed I can't expand thumbnails from Google Images. No pop-up with enlarged image opens. After disabling addon, all reverts to normal.

It's non-critical issue for me, but would be fun to know what's the problem. Maybe the addon accidentally overwrites some scripts on the page?

Other than that, I have a great fun making world seem more kind. Maybe another wish for addon is to be able read specified json dynamically, so you don't need to reimport every time you add new rule to json. Probably by setting some flag that should be off by default, because most users probably edit manually, not through json.

Thank you for your review.

The issue with the scripts is known but it should only happen if you use HTML in input and output or if you enable the replace scripts option. I would like to fix this problem but it's hard.

Regarding your second comment, you can use the update periodically from URL option. You can use a file:/// URL to access a local file.

Works Perfectly Rated 4 out of 5 stars

More fun than it probably should be. Got a (not) favourite forum troll? Or political candidate? Take childish delight in replacing their name with something suitably silly and demeaning. Or make your everyday reading less annoying by replacing words and phrases. Remove rude words. Or make them appear instead of euphemisms. An excellent tool to customise your online experience.

Doesn't work. Rated 1 out of 5 stars

Nothing gets replaced. It doesn't seem to do anything at all.

What are you trying to do? Which versions of Firefox and FoxReplace are you using? You should open an issue at if you have a problem.

Was working great. But now slows down certain pages. Rated 3 out of 5 stars

Especially on, FoxReplace will use so many resources that the page will hesitate for a second or two everytime I try to scroll, select text or type in a text box. There is even a delay when attempting to switch away from the tab of the problematic page. As a test, I disabled all add-ons, and the issue goes away. I restored the add-ons one-by-one and the issue only returns when FoxReplace is re-enabled. In another test, when I exclude the problematic page in the URL list - in this case with, the issue also goes away. But of course, IMDB is where I want FoxReplace to work as best as possible.

Maybe you have enabled periodic substitutions? Can you open a new issue at to try to research the problem?

Very handy tool. Rated 5 out of 5 stars

Make sure to check "Autoreplace on page load" on the main options screen. It seems to properly escape all escapable regex characters and works with a partial URL. I was able to change the background of the Pastebin edit button to light green.

Rated 5 out of 5 stars

This a great but potentially dangerous add-on as I'm sure other people wouldn't take too kindly to you "misreading" what they actually typed xD Aside from that, it's awesome; thanks!

halt the pages for many seconds Rated 4 out of 5 stars

recently this addon causes the pages that is trying to replace to hang for 15-18 seconds.
this happens when it tries to replace the words.
I have tested with the manual clinking on addon button and saw the delay myself.
this didn't happen before.
did I add too many replacement?
I just use it on a russian site for replacing russian words with persian ones

If it has started happening only recently and it didn't happen before, it probably has to do with a newer version of Firefox. I have to rewrite the addon to add real support for multiprocess Firefox, but it will take some time since there are many changes to do.

It's used to be perfect, but... Rated 4 out of 5 stars

I love this addon because i can censor many word that i don't like. But since the 0.17.2 update, some words in mobile version of facebook website and in texbox remain uncensored and it's not good. So please fix them so I can surf without any bad words

This review is for a previous version of the add-on (0.17.2). 

Indispensable Rated 5 out of 5 stars

So nice to be able to get rid of things like 'Just Sayin', changing things like 'totes' to 'totally', 'sorry not sorry' to 'sorry', and best of all goofy personalizations like.. changing 'Walmart' to 'The Zoo'. Awesome addon.

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

Best buy/Walmart/target #*$'$ PRICEMATCHING? Rated 5 out of 5 stars

Just a thought.. this could be the end to the box stores providing price matching services... None the less... Super app! Don't believe anyone else has done this on the mobile platforms as of yet.
Thumbs up to the dev.


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

A Must-Have for Political Campaign Season Rated 5 out of 5 stars

I see a lot of comments touting practical uses for this add-on, but it has some santiy-restoring humorous applications, too. Give all your least favorite politicians snarky nicknames! It makes reading the news a little more entertaining.

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

Generally good, though some bugs need fixing Rated 4 out of 5 stars

I've been using FoxReplace for about three years to correct common spelling errors, replace American spellings with British ones and hide racist slurs. It's one of my favourite extensions for Firefox.

It's generally worked well for me, though most recently I've seen the extension correct some instances of a word on a page and not others. I had to re-run the filter in order to have the words displayed properly.

There's also the issue that the filter doesn't seem to run on dynamic pages after the initial content has been loaded. The same applies to side-loaded content that's being embedded from another site; I'll still see the errors/unwanted variants/slurs even with the filter applied.

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

Saved me from property damage Rated 5 out of 5 stars

I was about to start smashing keyboards over ambiguous date formats, but this plugin let me change all dates to the proper format so I could calm down and let my blood pressure return to normal (quite literally).

As a Canadian I encounter dates in both d/m/Y format as well as m/d/Y so you never really know and it is incredibly frustrating.

With this tool I can figure out what the date format is for a particular website and set it to automatically correct the date to the proper, unambiguous Y-m-d format eliminating all confusion once and for all. I am finally at peace.

Thank you FoxReplace!!

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

Works great, but could use a tad more RegEx functionality Rated 4 out of 5 stars

I love this add-on. It's made the political primary season a lot more entertaining (reading about how Trump/Sauron won the nomination of the Death Eater Party, to the consternation of Elven and Dwarven Lords).

I'd love to have a little more functionality in the RegEx though. Specifically, being able to use lookbehind would be helpful (especially since this flavor already supports lookahead). Also, being able to use back-references (like incorporating parts of the matched text in the replacement) would be really useful (and could also replace the lookbehind feature...whichever is easier to implement).

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

It doesn't always work Rated 3 out of 5 stars

But it does, it's awesome.

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

Doesn't work as well as it used to Rated 3 out of 5 stars

When I first installed this, it worked pretty well. But recently, filtered words are beginning to slip through. A certain word starting with "f" started showing up, and wouldn't go away until I set up two separate entries for it. Also of not is that words that pop up on Google Images when an image is clicked used to be filtered, but now they're not for some reason. It's like FoxReplace is slowly deteriorating.

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

Very Good, it could be perfect Rated 4 out of 5 stars

I want to thank you for this amazing app. It is indeed pretty good. However, it may be perfect with a minor update. Just add an option to auto-replace after webpage loading (after it is totally loaded)

Option "Auto-replace on page load" doesn't always works well on some pages due to slow loading or action of some scripts which take some time after the loading. For these you may use the "Auto-replace every 'x' seconds". However it is so annoying having it working on the webpage for every 'x' seconds, and while it may be useful in some cases, it is not if the webpage is static. So for this I would add an option to do the replacing just once after you make sure the webpage is loaded (e.g., 'y' seconds after loading or just whatever the user wants).
It will be a 5-star app after this update.

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

Facebook issues Rated 4 out of 5 stars

This app is amazing and simple - once you figure out how to use it. I agree that it isn't quite straightforward. It takes some playing around to get to define what you want it to do.

However, the app doesn't work too flawlessly with Facebook. Since the site loads new info constantly, a simple "Auto-replace on page load" does not cover the incoming text from scrolling down to load new stories. Selecting "Auto-replace every X seconds" fixes this... but the issue with backwards writing is still present. Not sure if a new release was issued since this was addressed in Feb 2016 (I installed this on my new computer around May 1st), but just wanted to let you know the issue is still here.

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