message: Delete a file watcher.
diff: import * as vscode from 'vscode'
  import * as path from 'path'
  import { readFileSync } from 'fs'
  -import * as fs from 'fs'
  import { Extension } from '../main'
  import {replaceWebviewPlaceholders} from '../utils/webview'
  @@ -72,15 +71,6 @@ export class SnippetPanel {
  this.panel.webview.onDidReceiveMessage(this.messageReceive.bind(this))
  - fs.watchFile(webviewSourcePath, () => {
  - {
  - if (this.panel) {
  - const htmlStr = readFileSync(webviewSourcePath, { encoding: 'utf8' })
  - this.panel.webview.html = replaceWebviewPlaceholders(htmlStr, this.extension, this.panel.webview)
  - this.initialisePanel()
  - }
  - }
  - })
  }
  private mathSymbols: IMathSymbol[] = []
  