PlayCanvas is an HTML5 powered 3D game engine I featured a long time ago in the Closer Look game engine series. It has come a long way since then, and just now, received a much improved code editor. Usability improvements like the now ubiquitous tab view, an improved file navigator, improved code navigation and more.
From the announcement blog post:
Some of the new features introduced by the new editor:
File view & tabs
The most obvious difference is now we let you browse all your text files in the code editor and open multiple files in the same window. No more hunting through browser tabs to find that file you were editing.
Goto Anything (Ctrl/Cmd+P) is the power users dream option. Jump to any text file in your project with a few keystrokes.
Enhanced keyboard shortcuts
We’ve had a complete overhaul of the keyboard shortcuts. All your standard text editor shortcuts are there. Including using multiple cursors and expanding selections.
Better find & replace
We’ve beefed up the find and replace with a new interface and easy to use extras like case-sensitive and regular expressions.
You can learn more about PlayCanvas here.