Run this on the branches page of a GitHub repo to delete all merged or closed branches

delete-closed-branches.js

const rows = document.querySelectorAll("div[data-target='branch-filter.result'] .Box-row")

for (const r of rows) {
  const stateEl = r.querySelector(".State")
  if (stateEl && (stateEl.title.includes("Merged") || stateEl.title.includes("Closed"))) {
    r.querySelector(`button[data-target="branch-filter-item.destroyButton"]`).click()
  }
  
  //confirm("Continue?")
}