v1.8.17

What's Changed

• [1.x] fix: add xslt polyfill so forum continues to boot on browsers without XSLT by @imorland in #4644
• [1.x] fix(testing): use cookie for testing authentication by @huoxin233 in #4631
• [1.x] chore: peg composer version to LTS by @DavideIadeluca in #4661
• [1.x] Fix abandoned-extensions sync never being scheduled by @imorland in #4706
• [1.x] Add first-party Audit extension by @imorland in #4704
• [1.x] Fix broken images and Tests badge in README by @imorland in #4710
• [1.x] fix: mobile discussion total post count not updating on reply by @huoxin233 in #4684
• [1.x] fix(tooltip): resolve native tooltip flash, async teardown leaks, and dynamic text by @huoxin233 in #4675
• chore: prep 1.8.17 release by @imorland in #4735
• [1.x] Add docs link to Audit extension by @imorland in #4736

Full Changelog: v1.8.16...v1.8.17