Subscribe link of "Members' Activities" portlet is not working

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 6.2.10 EE GA1, 7.0.0 M3
• Fix Version/s: 7.0.0 M1
• Component/s: Activities widget, ~ [Archived] Social Networking
• Labels:
  • ee-ts
• Story Points: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/18816, https://github.com/brianchandotcom/liferay-plugins/pull/3223

Replication steps:
1. Deploy Social Networking portlet first. Then create a new site.
2. Add a blog or any other content to make sure there is at least one activity.
3. Drag a Members' Activities portlet to page and click "Subscribe to XX's activities"
Result: It will open a blank page.
Observation: This issue will not occur if there is also an "Activities" portlet be placed in the same page.