Disable Password Manager in Firefox Mobile

Just purchased LastPass premium and installed the Firefox Mobile extension. After about 20 minutes of use I'm already glad to have it. The soft keyboard that comes with the LastPass app (separate from the Firefox extension) looks like it will be very useful in the future.

This post is about the Firefox extension, and more specifically the Firefox password manager. When you install LastPass in the desktop version of Firefox, it asks if you want to disable the built in Firefox password manager. The mobile extension does not ask this (as of this post, 2013-3-21).
To manually disable the Firefox password manager (in the mobile version, and presumably in the desktop version as well)

1. Type in "about:config" in the address bar (without the quotation marks)
2. Search for "signon.rememberSignons" (also without quotes)
3. The default setting is "true". Click the "Toggle" button to switch it to default. 

This seems to do the trick. I only post this because a few minutes of Googling didn't find me the answer to this apparently uncommon question. I finally found the full list of about:config entries here: http://kb.mozillazine.org/About:config_entries

Here's to hoping I've saved someone else ten minutes.