I found it desirable to be able to delete entries from the history list.

Following is the code that seems to work for me:

(defun eww-history-delete-entry ()
"Delete an entry from the eww history list"
  (interactive)
  (cond
    ((equal (buffer-name) "*eww history*")
      (setq
        current-point (point)
        current-line  (- (line-number-at-pos (point-max))
                         (line-number-at-pos)))
      (with-current-buffer "*eww*"
        (setq eww-history (append
                (butlast eww-history current-line)
                (last    eww-history (1- current-line))))
              eww-history-position
                (min eww-history-position (1- current-line))
        (eww-list-histories)
        (goto-char current-point)))
    ((equal (buffer-name) "*eww*")
      (setq
        current-entry (- (length eww-history)
                         eww-history-position)
        eww-history   (append
          (butlast eww-history current-entry)
          (last    eww-history (1- current-entry))))
      (when (eq current-entry 1)
        (setq eww-history-position (1- eww-history-position))\
)
      (eww-restore-history
        (elt eww-history eww-history-position))
      (when (get-buffer "*eww history*")
        (eww-list-histories)))
    (t
      (user-error "Current buffer is neither the eww buffer, \
nor the eww history buffer"))))


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