If you mean the notes app Obsidian, looks like they support a type of plugins but only ones written in TypeScript. Our plugin framework Extism does allow plugins to be consumed from JavaScript but it’s hard to tell based on the Obsidian docs if their particular JS environment would support running arbitrary WASM plugins: like is it using Electron or node or a web view or something else. Their code is not open source so it’s hard to reason about. Hopefully there’s a good open source Nostr equivalent sometime soon!