DOM panel has a new option called Show inline event handlers (issue 4781).
There is a new Protocol column in the Net panel displaying HTTP protocol. You can use it to sort all requests and see e.g. all https request together (issue 4805)
Collision with RoboForm extension fixed (issue 4720)
It’s now possible to copy parts of JSON responses into the clipboard (issue 4689)
You can remove elements from the page while inspecting. Just start inspecting hover mouse over an element and press Delete key (issue 2212)
Internal architecture change: Firebug UI is running inside a frame element in order to isolate itself from other extensions. If you are developing Firebug extensions, see furtherinfo about this change.
Firebug 1.9a2 发布
getfirebug.com 已经有了Firebug 1.9a2!
Firebug 1.9a2 与Firefox 5 – Firefox 9 兼容，该版本修复了 23 个问题。
该版本重要改进如下：