Tether Versions Save

https://github.com/highlightjs/highlight.js/issues/2277

v2.0.0 (2021-03-26)

:bug: Bug Fix

• #713 Ensure parent still exists when removing event listeners (@drewjenkins)
• #692 Guard against undefined markers type (@rwwagner90)

:memo: Documentation

• #668 Remove Bootstrap from list (@MartijnCuppens)
• #600 Small Typo Fix (@SebYLim)

Committers: 5

• Andrew Jenkins (@drewjenkins)
• Martijn Cuppens (@MartijnCuppens)
• Robert Wagner (@rwwagner90)
• Sebastian Lim (@SebYLim)
• @dependabot-preview[bot]

Fixes the issue with Tether being used in server-side rendering when window and document are undefined

• Coffeescript -> ES6
• Proper UMD Wrapper
• Update build steps
• Add changelog
• Provide minified and unminified js/css