Script Summary: Provides a checkbox to UnMask password fields.
Using this Userscript provides a toggle to Unmask your password. Unmasking turns your password back from "••••••••" to "password" (or whatever your password actually is).
By default, your password will remain masked on any page unless you actually click the toggle checkbox.
DO NOT USE THE TOGGLE IN A CROWDED PLACE such as a Starbucks or airport terminal, because it will make your password visible to any stranger looking over your shoulder.
I know that will seem extremely obvious to the vast majority of you, but I feel like I should mention it just in case. You have been warned.
Displays oddly when visiting in to sites like Facebook.com, where the site hides the Password input until the user has selected the box that says "password". This is a form of inline labeling, and although it looks strange, it does not adversely affect the login process.
If you find a site where this script actually interferes with the login process (I sincerely doubt it, but there is a minuscule chance), please post a new Discussion mentioning the site that is impacted, and I will exclude that site from the script.
This is meant to be a small, mostly proof-of-concept script, and I do not have the time or desire to devise workarounds for every single site with a password box on it.
There will also be no custom CSS, so the text appended to the checkbox may seem out-of-place. If you wish to style it yourself with Stylish, the following is appended immediately after the Password input (the relevant HTML only):
<div class="GM_UnMask_Chk"><input type="checkbox">Unmask</div>