I was wondering, if there's anything in NPAPI, which supports reading/writing user settings? Currently I use XPCOM, but I want to get rid of this code in order to support other browsers than Firefox. I understand I can just read/write the file system (or registry on Windows) directly, but I want to explore other options - allowing the user edit these settings from the browser (e.g. about:config in FF) is, arguably, a better user experience than to direct him to edit some custom-made config files.
There is no such functionality in NPAPI.