diff --git a/models/issues/milestone.go b/models/issues/milestone.go
index 52433e735d..67a23246cf 100644
--- a/models/issues/milestone.go
+++ b/models/issues/milestone.go
@@ -67,6 +67,13 @@ type Milestone struct {
 	TotalTrackedTime int64 `xorm:"-"`
 }
 
+// Ghost milestone is a milestone which has been deleted
+const GhostMilestoneID = -1
+
+func (m *Milestone) IsGhost() bool {
+	return m.ID == GhostMilestoneID
+}
+
 func init() {
 	db.RegisterModel(new(Milestone))
 }
diff --git a/routers/web/repo/issue.go b/routers/web/repo/issue.go
index 3f17e30cec..5e228507c0 100644
--- a/routers/web/repo/issue.go
+++ b/routers/web/repo/issue.go
@@ -1693,7 +1693,7 @@ func ViewIssue(ctx *context.Context) {
 				return
 			}
 			ghostMilestone := &issues_model.Milestone{
-				ID:   -1,
+				ID:   issues_model.GhostMilestoneID,
 				Name: ctx.Locale.TrString("repo.issues.deleted_milestone"),
 			}
 			if comment.OldMilestoneID > 0 && comment.OldMilestone == nil {
diff --git a/templates/repo/issue/view_content/comments.tmpl b/templates/repo/issue/view_content/comments.tmpl
index aca77a92e5..2e9ba3dcd7 100644
--- a/templates/repo/issue/view_content/comments.tmpl
+++ b/templates/repo/issue/view_content/comments.tmpl
@@ -191,7 +191,31 @@
 				{{template "shared/user/avatarlink" dict "user" .Poster}}
 				<span class="text grey muted-links">
 					{{template "shared/user/authorlink" .Poster}}
-					{{if gt .OldMilestoneID 0}}{{if gt .MilestoneID 0}}{{ctx.Locale.Tr "repo.issues.change_milestone_at" .OldMilestone.Name .Milestone.Name $createdStr}}{{else}}{{ctx.Locale.Tr "repo.issues.remove_milestone_at" .OldMilestone.Name $createdStr}}{{end}}{{else if gt .MilestoneID 0}}{{ctx.Locale.Tr "repo.issues.add_milestone_at" .Milestone.Name $createdStr}}{{end}}
+					{{$newMilestoneDisplayHtml := ""}}
+					{{if gt .MilestoneID 0}}
+						{{if .Milestone.IsGhost}}
+							{{$newMilestoneDisplayHtml = .Milestone.Name}}
+						{{else}}
+							{{$newMilestoneDisplayHtml = HTMLFormat `<a href='%s/milestone/%d' rel='nofollow'>%s</a>` $.RepoLink .MilestoneID .Milestone.Name}}
+						{{end}}
+					{{end}}
+					{{$oldMilestoneDisplayHtml := ""}}
+					{{if gt .OldMilestoneID 0}}
+						{{if .OldMilestone.IsGhost}}
+							{{$oldMilestoneDisplayHtml = .OldMilestone.Name}}
+						{{else}}
+							{{$oldMilestoneDisplayHtml = HTMLFormat `<a href='%s/milestone/%d' rel='nofollow'>%s</a>` $.RepoLink .OldMilestoneID .OldMilestone.Name}}
+						{{end}}
+					{{end}}
+					{{if gt .OldMilestoneID 0}}
+						{{if gt .MilestoneID 0}}
+							{{ctx.Locale.Tr "repo.issues.change_milestone_at" $oldMilestoneDisplayHtml $newMilestoneDisplayHtml $createdStr}}
+						{{else}}
+							{{ctx.Locale.Tr "repo.issues.remove_milestone_at" $oldMilestoneDisplayHtml $createdStr}}
+						{{end}}
+					{{else}}
+						{{ctx.Locale.Tr "repo.issues.add_milestone_at" $newMilestoneDisplayHtml $createdStr}}
+					{{end}}
 				</span>
 			</div>
 		{{else if and (eq .Type 9) (gt .AssigneeID 0)}}
@@ -574,27 +598,33 @@
 				{{template "shared/user/avatarlink" dict "user" .Poster}}
 				<span class="text grey muted-links">
 					{{template "shared/user/authorlink" .Poster}}
-					{{$oldProjectDisplayHtml := "Unknown Project"}}
+					{{$oldProjectDisplayHtml := ""}}
 					{{if .OldProject}}
-						{{$tooltip := ctx.Locale.Tr "projects.deleted.display_name"}}
-						{{if not .OldProject.IsGhost}}
-							{{$tooltip = ctx.Locale.Tr (printf "projects.type-%d.display_name" .OldProject.Type)}}
+						{{if .OldProject.IsGhost}}
+							{{$tooltip := ctx.Locale.Tr "projects.deleted.display_name"}}
+							{{$oldProjectDisplayHtml = HTMLFormat `<span data-tooltip-content="%s">%s</span>` $tooltip .OldProject.Title}}
+						{{else}}
+							{{$tooltip := ctx.Locale.Tr (printf "projects.type-%d.display_name" .OldProject.Type)}}
+							{{$oldProjectDisplayHtml = HTMLFormat `<a href="%s/projects/%d" rel="nofollow"><span data-tooltip-content="%s">%s</span></a>` $.RepoLink .OldProjectID $tooltip .OldProject.Title}}
 						{{end}}
-						{{$oldProjectDisplayHtml = HTMLFormat `<span data-tooltip-content="%s">%s</span>` $tooltip .OldProject.Title}}
 					{{end}}
-					{{$newProjectDisplayHtml := "Unknown Project"}}
+					{{$newProjectDisplayHtml := ""}}
 					{{if .Project}}
-						{{$tooltip := ctx.Locale.Tr "projects.deleted.display_name"}}
-						{{if not .Project.IsGhost}}
-							{{$tooltip = ctx.Locale.Tr (printf "projects.type-%d.display_name" .Project.Type)}}
+						{{if .Project.IsGhost}}
+							{{$tooltip := ctx.Locale.Tr "projects.deleted.display_name"}}
+							{{$newProjectDisplayHtml = HTMLFormat `<span data-tooltip-content="%s">%s</span>` $tooltip .Project.Title}}
+						{{else}}
+							{{$tooltip := ctx.Locale.Tr (printf "projects.type-%d.display_name" .Project.Type)}}
+							{{$newProjectDisplayHtml = HTMLFormat `<a href="%s/projects/%d" rel="nofollow"><span data-tooltip-content="%s">%s</span></a>` $.RepoLink .ProjectID $tooltip .Project.Title}}
 						{{end}}
-						{{$newProjectDisplayHtml = HTMLFormat `<span data-tooltip-content="%s">%s</span>` $tooltip .Project.Title}}
 					{{end}}
-					{{if and (gt .OldProjectID 0) (gt .ProjectID 0)}}
-						{{ctx.Locale.Tr "repo.issues.change_project_at" $oldProjectDisplayHtml $newProjectDisplayHtml $createdStr}}
-					{{else if gt .OldProjectID 0}}
-						{{ctx.Locale.Tr "repo.issues.remove_project_at" $oldProjectDisplayHtml $createdStr}}
-					{{else if gt .ProjectID 0}}
+					{{if .OldProject}}
+						{{if .Project}}
+							{{ctx.Locale.Tr "repo.issues.change_project_at" $oldProjectDisplayHtml $newProjectDisplayHtml $createdStr}}
+						{{else}}
+							{{ctx.Locale.Tr "repo.issues.remove_project_at" $oldProjectDisplayHtml $createdStr}}
+						{{end}}
+					{{else}}
 						{{ctx.Locale.Tr "repo.issues.add_project_at" $newProjectDisplayHtml $createdStr}}
 					{{end}}
 				</span>
diff --git a/tests/integration/issue_comment_test.go b/tests/integration/issue_comment_test.go
index ee62b418f4..f77bfaa9bd 100644
--- a/tests/integration/issue_comment_test.go
+++ b/tests/integration/issue_comment_test.go
@@ -88,22 +88,19 @@ func TestIssueCommentChangeMilestone(t *testing.T) {
 	testIssueCommentChangeEvent(t, htmlDoc, "2000",
 		"octicon-milestone", "User One", "/user1",
 		[]string{"user1 added this to the milestone1 milestone"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/milestone/1"})
+		[]string{"/user1", "/user2/repo1/milestone/1"})
 
 	// Modify milestone
 	testIssueCommentChangeEvent(t, htmlDoc, "2001",
 		"octicon-milestone", "User One", "/user1",
 		[]string{"user1 modified the milestone from milestone1 to milestone2"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/milestone/1", "/user2/repo1/milestone/2"})
+		[]string{"/user1", "/user2/repo1/milestone/1", "/user2/repo1/milestone/2"})
 
 	// Remove milestone
 	testIssueCommentChangeEvent(t, htmlDoc, "2002",
 		"octicon-milestone", "User One", "/user1",
 		[]string{"user1 removed this from the milestone2 milestone"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/milestone/2"})
+		[]string{"/user1", "/user2/repo1/milestone/2"})
 
 	// Deleted milestone
 	testIssueCommentChangeEvent(t, htmlDoc, "2003",
@@ -123,22 +120,19 @@ func TestIssueCommentChangeProject(t *testing.T) {
 	testIssueCommentChangeEvent(t, htmlDoc, "2010",
 		"octicon-project", "User One", "/user1",
 		[]string{"user1 added this to the First project project"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/projects/1"})
+		[]string{"/user1", "/user2/repo1/projects/1"})
 
 	// Modify project
 	testIssueCommentChangeEvent(t, htmlDoc, "2011",
 		"octicon-project", "User One", "/user1",
 		[]string{"user1 modified the project from First project to second project"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/projects/1", "/user2/repo1/projects/2"})
+		[]string{"/user1", "/user2/repo1/projects/1", "/user2/repo1/projects/2"})
 
 	// Remove project
 	testIssueCommentChangeEvent(t, htmlDoc, "2012",
 		"octicon-project", "User One", "/user1",
 		[]string{"user1 removed this from the second project project"},
-		[]string{"/user1"})
-	// []string{"/user1", "/user2/repo1/projects/2"})
+		[]string{"/user1", "/user2/repo1/projects/2"})
 
 	// Deleted project
 	testIssueCommentChangeEvent(t, htmlDoc, "2013",