Firebug is like steel so heavy to use. Once I have accumlated enough logs the tool just starts lagging. Devtool is awesome but definitely still lack of some nice touch. I think there are still so much to improve with browser-side devtool. One annoying thing is (regardless of which browser, which devtool), editing stuff always happen in a small portion of a screen. If we can have a dedicated devtool app that'd be awesome. Bigger font, more tabs, drag and drop placement / customized view), and with extension (You should be able to do that already, don't remember).

Sure you can drag the devtool out, but it still lives as part of the browser windows, and switching back and forth between several instances of browser windows? tough! I am not sure, but has Mozilla hired the folks behind Firebug already?

Cookie editing is still missing. Without this feature a wider adoption of FF dev tools or its full utility as a wedev tool is impossible. Yes, I voted for https://bugzilla.mozilla.org/show_bug.cgi?id=1031192. Please do the same. Thanks.

I keep an old copy of Firefox around just so I can have Firebug 2.

Here's what I'd like DevTools to do:

* Make a breakpoints view, not one embedded into a massive list of unsorted (or sorted-by-load-date I guess?!) files that changes over time. If that can't be done (or is against the design philosophy of DevTools), letting me choose the sort order would be nice (e.g. recently-viewed files first, or files with breakpoints, etc ..... and uh, remembering those files and/or settings through refreshes would be fantastic... I miss it from Firebug 2). It's nice because after/during refreshes the breakpoint view lets you pull up the file the second it's loaded, instead of scrolling around in the file list until you find it.

* Make it a LOT more obvious when DevTools is stopped at a breakpoint.

* DevTools doesn't handle initial focus the way Firebug does. As in, when you pull up Firebug via the selection icon--oh, DevTools needs that selection icon for the toolbar--it goes straight to the dom node you selected.

* Make DevTools stop crashing. It stops working. Constantly. The console will just stop printing output, and the DOM view just stops displaying HTML, requiring a browser restart. (When this happens, if you, say, pull up the console and type "1" and hit enter, usually the console echos "1" back to you. When you're in this state, it's not echoed back, though, oddly, some script messages still pop in.)

* Make "debugger" start working again. There are some places where--for who knows what reason--both Firebug and DevTools have ignored breakpoints I've put in, and I've been able to get around it in Firebug by explicitly putting in "debugger;" into my code. You definitely know you're in deep kimchi when you need "debugger;".

* Make DevTools remember the state of my "Log Response/Request Bodies" checkbox. It gets reset constantly, and it should be remembered across refreshes. Heck, even by URL. If I turn it on, leave it on.

Also, for one of my websites, it can't load the source. It just shows "eval" as the filenames over and over with nothing in them. Firebug 2 loads it just fine.

Long live Firebug 2!

I still can't seem to view websocket frames with DevTools. It's the only thing I switch to Chrome dev tools for. Am I alone?

I've started developing in FF because of the ability to not have all my chrome plugins installed everywhere, and the dev tools are pretty much there compared to chrome a few versions ago.

For performance inspection chrome is still the winner for sure, but when I just want a light fast experience, FF has been great the last few months.

> Firebug 3 is not another developer tool, it is rather a thin layer built on top of DevTools.

Why I feel it's terrible news?

I feel like this is a promise of less features for more bugs without any clear vision about why Firebug should be ditched in favor of DevTools.

What really bother me with Firebug and Firefox-debugging is that I can't see when the debugger pauses my page.

So when I'm testing and the debugger fires, I'd still be clicking stuff on my page, wondering why it isn't responding.

I just checked and Debugger -> Sources is still a single alphabetical list. This makes it unusable on a non-trivial JavaScript app that will easily have 50+ modules.

There is no reason to still use Firebug in 2015 besides laziness.

Firebug has several little features that aren't available in FF DevTools nor Chrome DevTools. Let's hope Firebug 3 has no feature regression and stays around.

Thanks Mozilla, exciting developments! I really enjoy the Firebug user experience, and am looking forward to having it be the frontend to the developer tools.