message: Fix activity feeds not working in SSR context.
diff: @@ -14,7 +14,7 @@ const MaxCachedCount = 3;
  interface ActivityFeedState {
  key?: string;
  - href: string;
  + href?: string;
  container: ActivityFeedContainer;
  }
  @@ -147,7 +147,7 @@ export class ActivityFeedService {
  private static makeState(items: ActivityFeedInput[], options: ActivityFeedContainerOptions) {
  const key = this.getStateKey();
  - const href = window.location.href;
  + const href = typeof window !== 'undefined' ? window.location.href : undefined;
  const state = {
  key,
  @@ -164,7 +164,7 @@ export class ActivityFeedService {
  private static findState() {
  const key = this.getStateKey();
  - const href = window.location.href;
  + const href = typeof window !== 'undefined' ? window.location.href : undefined;
  // Note that we have to check the history state key AND the actual URL. If you replace a
  // route with vue, the history state key stays the same, even though the route changes.
  