Method flatten

external/.scrollLibs.js:14276–14279

(arr)

    return del
  }
  static flatten(arr) {
    if (arr.flat) return arr.flat()
    return arr.reduce((acc, val) => acc.concat(val), [])
  }
  static escapeBackTicks(str) {
    return str.replace(/\`/g, "\\`").replace(/\$\{/g, "\\${")
  }