Merge pull request #427 from lyricat/patch-1

 README/extensions: Add goldmark-enclave

README.md

@@ -491,6 +491,7 @@ Extensions
 - [goldmark-d2](https://github.com/FurqanSoftware/goldmark-d2): Adds support for [D2](https://d2lang.com/) diagrams.
 - [goldmark-katex](https://github.com/FurqanSoftware/goldmark-katex): Adds support for [KaTeX](https://katex.org/) math and equations.
 - [goldmark-img64](https://github.com/tenkoh/goldmark-img64): Adds support for embedding images into the document as DataURL (base64 encoded).
+- [goldmark-enclave](https://github.com/quail-ink/goldmark-enclave): Adds support for embedding youtube/bilibili video, X's [oembed tweet](https://publish.twitter.com/), [tradingview](https://www.tradingview.com/widget/)'s chart, [quail](https://quail.ink)'s widget into the document.
 
 ### Loading extensions at runtime
 [goldmark-dynamic](https://github.com/yuin/goldmark-dynamic) allows you to write a goldmark extension in Lua and load it at runtime without re-compilation.