Google has switched on extension support for the Mac edition of Chrome, bringing that version in line with those for Windows and Linux.

In a notice posted to the Google Chrome Releases blog, Anthony Laforge, a Chrome program manager, spelled out the newest changes to the "dev" version of Chrome. Among the new features are extension support and bookmark synchronisation between multiple machines, another tool that had been missing from Chrome for the Mac.

When Google shipped the first beta of Chrome for the Mac a month ago, it omitted extension support, although add-ons could be installed on the Windows and Linux versions of the browser.

Google uses three build "channels" to distribute Chrome: stable, beta and dev, in descending order of stability. According to Google, the dev channel "can be very unstable at times" and "may require some manual configuration."

The dev channel edition of Chrome lives up to its label; according to Laforge, the Mac preview crashes when the user adds a new bookmark folder if sync is enabled.

Chrome accounted for 4.6% of all browsers used in December, web measurement company Net Applications said last week, enough to push it past Apple's Safari and into the No. 3 spot behind Microsoft's Internet Explorer and Mozilla's Firefox.

Mac users who want to try the new dev build of Chrome must "subscribe" to the dev channel by downloading and installing the latest developer edition. Google said it is working on bringing extensions to the beta of Mac Chrome, but did not specify a timetable.

Once the dev version is installed, Chrome extensions can be downloaded from Google's site.