Mozilla this week released the antipenultimate alpha edition of Firefox 3.0. Alpha 5 of Firefox 3.0 includes a major chunk of the web browser's revamped bookmark and history tools.

Alpha 5 of Firefox 3.0 carries the codename Gran Paradiso. The Firefox 3.0 preview includes the bookmarks portion of Places, a feature at one point expected to appear in Firefox 2.0. Mozilla removed the searchable bookmark-browser history from Firefox 2.0, however, and said it would appear in 2007's Firefox 3.0 release.

Mozilla warned users to back up existing Firefox bookmarks before testing the alpha. Because Places uses the open-source SQLite database engine to store and retrieve bookmarks and history entries, it's incompatible with earlier Firefox editions' bookmarks.

"There are rough edges [to Places]; please wear your hard hat at all times," a warning urged. "Remember that the UI is still being designed, and don't be surprised to find some regressions, both functional and in performance."

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Alpha 6 of Firefox 3.0, which is to debut on 29 June, will bake in the remainder of Places, including indexing of bookmarks and history logs, tagging and metadata search.

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The Alpha 5 release of Firefox 3.0 also includes a crash-reporting system to help Mozilla sort out problems, a new JavaScript-based Password Manager and several improvements to the Mac OS X edition. Windows, Mac and Linux versions of Firefox 3.0 Alpha 5 can be downloaded from the Mozilla site.

Mozilla this week also spelled out what Firefox 1.5 users will soon see when the auto-update mechanism is activated in the next few weeks. Users will choose whether to update the browser to 2.0, delay the update or permanently reject it. Firefox 1.5 support ended last month, and Mozilla is trying to get all users to upgrade to the current browser.

According to the Firefox 3.0 production schedule, Alpha 5 was several days late. One more alpha is planned before Beta 1 debuts 31 July.

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