Firefox 3.0 recorded usage share of web browsers. Estimates of Firefox 3.0's global market share were generally in the range of 4–5%, and then dropped as users migrated to Firefox 3.5 and later Firefox 3.6. Partially as a result of this, between mid-December 2009 and the end of January 2010, Firefox 3.5 was the most popular browser (when counting individual browser versions), passing Internet Explorer 7. Mozilla ended support for Firefox 3 on March 30, 2010 with the release of 3.0.19. Firefox 3.0 was developed under the codename "Gran Paradiso". This, like other Firefox codenames, is the name of an actual place;
Kerning some complex typesetting functions that may be hard to implement through plug-ins (kerning in particular) may be relatively easy to implement through separate tools. The CSS property codice_1 enables kerning in Firefox, Chrome, Safari, Opera, and the Android Browser. There is also a proposed CSS3 property codice_2, but it is only supported in Firefox (prefixed with codice_3), Chrome and Opera (prefixed with codice_4 in both) and in Internet Explorer starting at version 10. The CSS3 draft suggests that kerning should always be enabled for OpenType fonts. The human perception of kerning can vary with the intraword and interword spacing during