Hi @ffledgling,

So when you write into the file, for booleans and numbers, no quotes should be in the final output:

pref("browser.cache.disk.enable", true);
pref("browser.cache.disk.capacity", 55000); // kilobytes
pref("browser.cache.disk.parent_directory", "/cache");

The string "/cache" must be surrounded in quotes, but the 55000 and true shown above must not be in quotes.