diff --git a/modules/forgefed/star.go b/modules/forgefed/star.go
index e0001c7cbb..7444e32de4 100644
--- a/modules/forgefed/star.go
+++ b/modules/forgefed/star.go
@@ -6,6 +6,7 @@ package forgefed
 import (
 	"code.gitea.io/gitea/modules/context"
 	ap "github.com/go-ap/activitypub"
+	"github.com/valyala/fastjson"
 )
 
 type (
@@ -64,3 +65,23 @@ func (a Star) MarshalJSON() ([]byte, error) {
 	ap.JSONWrite(&b, '}')
 	return b, nil
 }
+
+func JSONLoadStar(val *fastjson.Value, s *Star) error {
+	if err := ap.OnActivity(&s.Activity, func(a *ap.Activity) error {
+		return ap.JSONLoadActivity(val, a)
+	}); err != nil {
+		return err
+	}
+
+	s.Source = SourceType(ap.JSONGetString(val, "source"))
+	return nil
+}
+
+func (s *Star) UnmarshalJSON(data []byte) error {
+	p := fastjson.Parser{}
+	val, err := p.ParseBytes(data)
+	if err != nil {
+		return err
+	}
+	return JSONLoadStar(val, s)
+}
diff --git a/modules/forgefed/star_test.go b/modules/forgefed/star_test.go
index 04e6373778..6727e79e12 100644
--- a/modules/forgefed/star_test.go
+++ b/modules/forgefed/star_test.go
@@ -48,3 +48,43 @@ func Test_StarMarshalJSON(t *testing.T) {
 		})
 	}
 }
+
+func Test_StarUnmarshalJSON(t *testing.T) {
+	type testPair struct {
+		item    []byte
+		want    Star
+		wantErr error
+	}
+
+	tests := map[string]testPair{
+		"empty": {
+			item: []byte(``),
+			want: Star{},
+		},
+		"with ID": {
+			item: []byte(`{"source":"forgejo","type":"Star","actor":"https://repo.prod.meissa.de/api/activitypub/user-id/1","object":"https://codeberg.org/api/activitypub/repository-id/1"}`),
+			want: Star{
+				Source: "forgejo",
+				Activity: ap.Activity{
+					Actor:  ap.IRI("https://repo.prod.meissa.de/api/activitypub/user-id/1"),
+					Type:   "Star",
+					Object: ap.IRI("https://codeberg.org/api/activitypub/repository-id/1"),
+				},
+			},
+		},
+	}
+
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+			got := new(Star)
+			err := got.UnmarshalJSON(tt.item)
+			if (err != nil || tt.wantErr != nil) && tt.wantErr.Error() != err.Error() {
+				t.Errorf("UnmarshalJSON() error = \"%v\", wantErr \"%v\"", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("UnmarshalJSON() got = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}