Disable IPv6-Support in about:config:

• network.dns.disableIPv6 = true

– via MozillaZine forums, also see MozillaZine Knowledge Base

• Originally from here, simply adjusted a bit for scuttle and merged together from two different bookmarklets by me
• Copy this to an editor of your choice:

  javascript:
  user='foo';
  password='bar';
  server='scuttle.org';
  tags='%s';
  url=location.href;
  extended='' + (window.getSelection) ? window.getSelection() : 
  ((document.getSelection) ? document.getSelection() : document.selection.createRange().text);
  title=document.title;
  apistring='http://'+user+':'+password+'@'+server+'/api/posts/add?url=' 
  +encodeURIComponent(url)+'&description='+encodeURIComponent(title)+
  '&tags='+encodeURIComponent(tags)+'&extended='+encodeURIComponent(extended);
  location.href=apistring;

  Now insert your account data (user and password need to be set) and adjust the server location, if you don't use scuttle.org. Then remove all newlines and add the resulting one-line-bookmarklet as a bookmark to your browser and assign a search keyword to it, e.g. add
  

• Now you can add the page currently opened by simply typing something like add tag1 tag2 tag3 into the browsers location bar. The new bookmark gets automatically tagged with the tags you entered after the search keyword. If you have any text selected on the page you are bookmarking, it is used as the extended description.

Firefox 2.0 introduces a new about:config variable (or maybe it was there before and I just didn't see it…), ui.allow_platform_file_picker. Settings this to false brings back the old Firefox filepicker after a restart of the browser.

With version 1.5, Firefox now uses the GTK Filepicker under linux instead of the built in one. Sadly though, this thing is slow as hell (and imo not as usable as well). Here you can find how to reenable the old one. Summary:

• Edit nsFilePicker.js in the components directory (that would be /usr/lib/firefox/components on Debian¹⁾), and change

      compMgr.registerFactoryLocation(FILEPICKER_CID,
                                      "FilePicker JS Component",
  //@line 278 [...]
                                      "",
  //@line 280 [...]
                                      fileSpec,
                                      location,
                                      type);

  to

      compMgr.registerFactoryLocation(FILEPICKER_CID,
                                      "FilePicker JS Component",
  //@line 278 [...]
                                      FILEPICKER_CONTRACTID,
  //@line 280 [...]
                                      fileSpec,
                                      location,
                                      type);

• Make Firefox re-register its components (e.g. by disabling and - after a restart of Firefox - re-enabling an extension of your choice, or simply by installing a new one)
• Enjoy the brought back Firefox-filepicker.

A list of my currently installed extensions can be found here.

• Problem: Hit-a-Hint doesnt do a thing although installed successfully
• Solution: Use

  //*[@href] | //*[@onclick] | //*[@onmousedown] | //*[@onmouseup] | //*[@oncommand] | //input | //frame | //iframe | //textarea | //button | //select | //*[@class='lk'] | //*[@class='s']

  in Hit-a-Hint Preferences > Hint Options > XPath of the tags to be hinted

• Source: Comment 54 @ HaH Mozdev Project Site

You can easily add quicksearches by right-clicking into a searchform and selecting “Add a Keyword for this Search…”. You then simply assign a name and a keyword to the search and you're done. Currently the following quicksearches are defined in my FF:

• g: Google
• gi: Google Images
• w: Wikipedia
• wd: German Wikipedia
• leo: dict.leo.org
• add: scuttle-add-bookmarklet
• ani: AniDB
• imdb: IMDB

• ui.allow_platform_file_picker = false: Disables platform specific (e.g. Gnome-) filepicker and instead uses the (fast) builtin one
• network.dns.disableIPV6 = true: Disables IPV6 DNS queries. Can prevent IPV6 related connection timeouts
• browser.backspace_action = 0: Pressing Backspace will result in one step back in the browser history (1 makes backspace do a page-up)

• Greasemonkey Userscripts