[Backport] Fixing new membership in timelines

taiga/timeline/service.py

@@ -115,6 +115,10 @@ def filter_timeline_for_user(timeline, user):
                                             project__anon_permissions__contains=[content_type_key],
                                             data_content_type=content_type)
 
+    # There is no specific permission for seeing new memberships
+    membership_content_type = ContentType.objects.get(app_label="projects", model="membership")
+    tl_filter |= Q(project__is_private=True, data_content_type=membership_content_type)
+
     # Filtering private projects where user is member
     if not user.is_anonymous():
         membership_model = apps.get_model('projects', 'Membership')

tests/integration/test_timeline.py

@@ -125,7 +125,7 @@ def test_filter_timeline_private_project_member_permissions():
     service._add_to_object_timeline(user1, task2, "test")
     timeline = Timeline.objects.all()
     timeline = service.filter_timeline_for_user(timeline, user2)
-    assert timeline.count() == 1
+    assert timeline.count() == 3
 
 
 def test_create_project_timeline():