Removing "How" is one of those automatic edits to titles made by HN, and I think it's a bad idea, as it often changes the meaning. Fortunately, it's possible to for the submitter to click "edit" and change it back to the original.

HN does this automatically when you submit a title starting with “How”. I guess it reduces the clickbaityness of certain types of titles, but fails in cases like these.

If it happens and you don’t like it you can edit the submission to add the word back.