# Deno v1.13.1 — Release & Upgrade Intelligence
- **Product:** Deno (https://deno.com)
- **Version:** v1.13.1
- **Released:** Aug 16, 2021
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/deno/updates/v1.13.1/

## Executive Summary (TL;DR)
Deno v1.13.1. Source highlight: fix: Blob#slice arguments should be optional (#11665)

## Improvements
- perf: improve localStorage throughput (#11709)
- perf(ext/http): faster req_url string assembly (#11711)

## Bug Fixes
- fix: Blob#slice arguments should be optional (#11665)
- fix: correct spelling of certificate in `--unsafely-ignore-certificate-errors` warning message (#11634)
- fix: don't statically type name on Deno.errors (#11715)
- fix: parse error when transpiling code with BOM (#11688)
- fix(cli): allow specifiers of unknown media types with test command (#11652)
- fix(cli): explicitly scan for ignore attribute in inline tests (#11647)