message: Remove Viewer.clients
diff: @@ -130,18 +130,6 @@ export class Viewer {
  }
  }
  - /**
  - * Only for backward compatibility.
  - * @deprecated
  - */
  - get clients(): { [key: string]: Set<unknown> } {
  - const ret = Object.create(null) as { [key: string]: Set<unknown> }
  - this.clientMap.forEach((clientSet, key) => {
  - ret[key] = new Set(Array.from(clientSet).map(() => Object.create(null) as unknown ))
  - })
  - return ret
  - }
  -
  /**
  * Returns the set of client instances of a PDF file.
  * Returns `undefined` if the viewer have not recieved any request for the PDF file.
  