There is absolutely not a single developer in the world who knows what size I like my browser, although many people think they do. To prevent resizing of FF make the following steps.

1. Open browser preferences
2. Choose "Content"
3. Choose "Advanced" on the "Enable javascript" preference
4. Untick "Move or resize existing windows"

Create a new profile for extension development

http://lifehacker.com/software/firefox/geek-to-live%E2%80%94manage-multiple-firefox-profiles-231646.php

Tweak Firefox configuration for extension development

http://developer.mozilla.org/en/docs/Setting\_up\_extension\_development\_environment

Create a skeleton extension

http://ted.mielczarek.org/code/mozilla/extensionwiz/

Extract it to the your project folder, for example:

/home/name/projects/my_extension

Setup Firefox to load your extension

Follow these instructions to configure Firefox to load your extension from /home/name/projects/my_extension: http://developer.mozilla.org/en/docs/Setting\_up\_extension\_development\_environment\#Custom\_code\_location http://developer.mozilla.org/en/docs/Setting\_up\_extension\_development\_environment\#Using\_directories\_rather\_than\_JARs

Install the Extension developer

http://ted.mielczarek.org/code/mozilla/extensiondev/

Start Firefox with the development profile

firefox-bin -P development -no-remote

To start the default profile use:

firefox-bin -P THE_PROFILE_NAME -no-remote

Build your extension

http://www.xulplanet.com/

The extension wizard includes a build script, but it might be a good idea to upgrade it to the latest version, which can be found here (including a Windows build script): http://kb.mozillazine.org/Bash\_build\_script

Gotchas

If you're on windows and using CygWin, you might get this error:

./build.sh: line 6: $'\r': command not found
./build.sh: line 29: $'\r': command not found
./build.sh: line 40: $'\r': command not found
./build.sh: line 70: syntax error near unexpected token $'do\r''
'/build.sh: line 70: for CHROME_SUBDIR in $CHROME_PROVIDERS; do

The solution is to run the dos2unix command on the *.sh files:

d2u build.sh
d2u config_build.sh

Note that this only works from a Firefox extension:

function openTab(url, focus) 
  {
    var tab = getBrowser().addTab(url);

    if(focus)
    {
      getBrowser().selectedTab = tab;
    }
   
    return tab;
  }

Firefox hogs a lot of memory when using pages using Ajax enabled web pages. I need to restart the browser many times during a day at the office. This hack seems to have fixed that issue.

Open the location about:config, right click and create a new key of integer type.

Key:

browser.cache.memory.capacity

Value:

16384

It's really simple to use GPG to encrypt and/or sign email you send through Gmail.

Generate your private key.

gpg --gen-key

Extract your public key, which you will send to people you need to communicate securely with.

gpg --armor --export [email protected] > my_public_pgp_key

Install FireGPG and restart the browser. Use GPG in Gmail.

# Start the development profile
/Applications/Firefox.app/Contents/MacOS/firefox-bin -P 'development'
# Choose the profile manually
/Applications/Firefox.app/Contents/MacOS/firefox-bin -ProfileManager

Extensions slow down Firefox so I prefer disabling all but the most important Firefox extensions when coding.

Here's how to do it:

1. First, create a development profile following these instructions http://support.mozilla.com/en-US/kb/Managing+profiles

1. Next, create a shortcut that starts Firefox in development mode:

# Mac OSX
/Applications/Firefox.app/Contents/MacOS/firefox-bin -P development -no-remote

# Linux
/usr/lib/firefox/firefox-bin -P development -no-remote

# Windblows
"C:\Program Files\Mozilla Firefox\firefox.exe" -P development -no-remote

To force Firefox to show your updated favicon (updating favicon.ico is not enough), first quit Firefox. Then issue the following commands in the terminal:

$ cd /Volumes/Macintosh\ HD/Users/christian/Library/Application\ Support/Firefox/Profiles/46xov8kt.default
$ sqlite3 places.sqlite 
SQLite version 3.5.0
Enter ".help" for instructions
sqlite> 
sqlite> delete from moz_favicons;
sqlite> update moz_places set favicon_id = NULL;
sqlite> .quit

Firefox 3.1 supports the geolocation API specification.

Try copying this code and running it in Firebug:

function showMap(position) {
  // Show a map centered at (position.coords.latitude, position.coords.longitude).
  console.dir(position);
}

navigator.geolocation.getCurrentPosition(showMap);

Jetpack extension:

jetpack.future.import('menu');
jetpack.future.import('selection');
 
jetpack.menu.context.page.on('img').add(function(target) ({
  label:   "Post to flickr.com",
  icon:    "http://xxx/icon.png",
  command: function() {
    var url = "http://flickr.com/api?";

    var selectedText = jetpack.selection.text || '';
    var sourceImage   = target.node.src;
    var sourcePage = jetpack.tabs.focused.url;

    url += encodeURI('image') + '=' + encodeURI(sourceImage);
    url += '&' + encodeURI('description') + '=' + encodeURI(selectedText.substr(0, 200));

    jetpack.tabs.open(url).focus(); 
  }
}));

Installation page:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html lang="en">
<head>
    <title>The Jetpack Feature</title>
    <link rel="jetpack" href="/javascripts/jetpack-extension.js" name="com extension" />
</head>
<body>
</body>
</html>