How can I write my HTML login form to explicitly enable LastPass?

Question

How can I write my HTML login form to be guaranteed to work with LastPass, or at least make it as likely as possible to work? Some sites require the "Save All Entered Data" to work properly with LastPass, but as a site developer I'm looking for something better. What do I need to do to ensure LastPass default mode ("Save Site") works as flawlessly as possible? I can't find any official documentation, or really even any good blog posts with suggestions, but that would certainly answer my question. What does ideal or at least empirically successful markup look like?

Extra credit for (1) evidence and/or (2) a strategy that works across multiple password managers.

Answer 1

Finally found official support statement. Excerpt:

<form action="https://mypage.com/blah" method="post">
  <input type="text" name="username" id="username" value=""/>
  <input type="password" name="password" id="password" value=""/>
  <input type="submit" value="LOGIN"/>
</form>

This closely related question is also really helpful for general advice across all password managers.