The editor is written in Java, so you can run it as an applet in your browser. Due to the security limitations, when you run the editor in this way, some functionality will not work such as cut&paste and Java will often mix up file names and extensions when loading and saving things.
The preferred way to run this program is to download it. You can double-click the downloaded .jar file to run it.
I'm bad at naming things, so I'll give a proper name to the editor as soon as I think of something (I'll probably name it after the first game I write with it).
I'll put up the source code for this program later after I have had to time to clean it up a bit.
The editor is released under the terms of the CC0 so that you should feel free to use the [insert name] IF Editor however you choose and that no restrictions are imposed on what you do with your IF code and HTML generated from it.
To the extent possible under law, Ming-Yee Iu has waived all copyright and related or neighboring rights to [insert name] IF Editor.