Word frequency counter

Words are runs of letters and numbers, with apostrophes and hyphens kept inside a word, so don't and well-known each count once. Percentages are each word's share of the words actually counted, that is after the stop-word filter, not before. The stop-word list is a short built-in English set, not a configurable dictionary, and the ranking is by count with ties in first-appearance order. Everything runs in this tab; the text never leaves the browser.