Firefox 17 has recently entered the Aurora channel and comes a number of improvements to the built-in web developer tools.
Aurora is the codename for the upcoming version of Firefox and at the moment it is home to version 17.0a2.
A new Markup Panel for HTML editing is among Firefox 17's new features. It opens either with Ctrl-M or when you open the Page Inspector and click on an icon representing outline and it lets you manipulate the DOM on the page.
The Markup Panel brings other editing capabilities. According to the Mozilla Blog:
Previously, you could double click on an attribute value to change that value. Now you can double click almost anywhere to change anything. Double click on text to change the text. Likewise for the tag itself. See that space just before the closing “>” of a tag? Double click there and you can add new attributes.
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Although the above screenshot shows the Markup panel with a dark theme, the plan is to replace it with a light theme before release.
Firefox 17 also sees improvements to the Web Console, including a refreshed toolbar giving it the same "look" as the rest of the Firefox developer tools, and the ability to zoom in to it, better autocompletion and a change to the $ helper function which now has more helpful behavior.
Other notable improvements are to the debugger - it now searches across all scripts when you start a search with the ! (exclamation mark) and has extra keyboard shortcuts.
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While on the topic of the debugger, the problem in Firefox 15 of the dubugger not hitting its breakpoints on page reload is fixed in Firefox 16 which is currently in beta.
Firefox 17 will be released later in the year but if you can't wait until then for the new developer features, it can be downloaded from Aurora.
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