I'll refer you to this bug I just posted:
When assisting with chasing down bugs, I have often been asked to make settings changes in various config files. Often, the instructions I'm given are incomplete, there are multiple different config files in very different places, they are in different places on different platforms, and the settings often just don't work, probably because the devs who suggest what to set are too familiar with the system and don't realize what the uninitiated don't know, so they leave out too many details or make mistakes they don't realize are important. Having to muck around with these obscure text files, adding obscure strings to obscure variables is WAY too error-prone.
Instead, what NetBeans needs is something very much like Firefox's about:config page. By opening this, every possible variable with every possible value (or free-form text field) becomes accessible.
This will make NetBeans a LOT more user-friendly for debugging, and it'll also help in obscure cases with stable versions when users need unusual settings.
Since I use the development builds of NetBeans, I end up often reporting multiple bugs a day, and some of the bugs I've reported have been out-standing for a long time. I think NetBeans could stand to have some improvements that make it easier on both developers and users to track down bugs.
I agree that an editor like about:config would be found practical by many users. This is nevertheless more complex than it seems - offering valid values only, for instance, would require excessive change of config files handling. But the idea of presenting various sources of settings in one page is worth thinking over.
Sometimes you'll just have to allow the user to enter a free-form string, because you can't know all the possible valid options. That's okay. The problems with editing config files are:
1. Finding which config file to edit
2. Knowing which environment variable to modify
3. Knowing the proper syntax for modifying that variable
4. Knowing name of the config variable to add or edit
5. Knowing the proper syntax for that
6. Knowing what values are valid
By adding a free-form text field for some variables, you solve 1 through 5. Huge step forward.