Webview persistence: Webview won't be reconstructed when reloading more than once

[octref]

#50696

I have a serializer like this registered:

  vscode.window.registerWebviewPanelSerializer(CatCodingPanel.viewType, {
    deserializeWebviewPanel(webviewPanel: vscode.WebviewPanel, state: any) {
      console.log(state)
      webviewPanel.webview.html = '<div>hi</div>'
      return Promise.resolve()
    }
  })

[mjbvz]

I believe this was fixed by 6e81adc

Marking as duplicate of #50752