setq w3m-form-input-textarea-buffer-lines 111

[jidanni@xxxxxxxxxxx]

Even if one does (setq w3m-form-input-textarea-buffer-lines 111),
there will still be 2 lines of the calling window, which indeed is
fine with me. But still Info should mention how to make the
textarea-buffer 100% of the screen.

P.S., In Info we see
      Unless `w3m-form-use-textarea-backup' is set to `nil', emacs-w3m
   stores the text you input in textareas in backup files for later reuse.
   When you start editing a form and there is backup text available, you
   will be asked whether you want to use it or not.  Files to save text
   are stored in the directory specified by the
   `w3m-form-textarea-directory' variable.
Also mention how long they are preserved, 100 years :-) ?