diff --git a/models/fixtures/comment.yml b/models/fixtures/comment.yml
index 2c47196c05..34407d6f81 100644
--- a/models/fixtures/comment.yml
+++ b/models/fixtures/comment.yml
@@ -153,3 +153,304 @@
   issue_id: 19 # in repo_id 58
   content: '{"is_force_push":true,"commit_ids":["1978192d98bb1b65e11c2cf37da854fbf94bffd6", "9b93963cf6de4dc33f915bb67f192d099c301f43"]}'
   created_unix: 1749734240
+
+-
+  id: 2000
+  type: 8 # milestone
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  milestone_id: 1
+  old_milestone_id: 0
+  created_unix: 946684820
+
+-
+  id: 2001
+  type: 8 # milestone
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  milestone_id: 2
+  old_milestone_id: 1
+  created_unix: 946684920
+
+-
+  id: 2002
+  type: 8 # milestone
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  milestone_id: 0
+  old_milestone_id: 2
+  created_unix: 946685020
+
+-
+  id: 2003
+  type: 8 # milestone
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  milestone_id: 10 # not exsting milestone
+  old_milestone_id: 0
+  created_unix: 946685080
+
+-
+  id: 2010
+  type: 30 # project
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  project_id: 1
+  old_project_id: 0
+  created_unix: 946685120
+
+-
+  id: 2011
+  type: 30 # project
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  project_id: 2
+  old_project_id: 1
+  created_unix: 946685220
+
+-
+  id: 2012
+  type: 30 # project
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  project_id: 0
+  old_project_id: 2
+  created_unix: 946685320
+
+-
+  id: 2013
+  type: 30 # project
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  project_id: 10 # not existing project
+  old_project_id: 0
+  created_unix: 946685420
+
+-
+  id: 2020
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  label_id: 1
+  content: 1 # add label
+  created_unix: 946685520
+
+-
+  id: 2021
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1
+  label_id: 2
+  content: 1 # add label
+  created_unix: 946685620
+
+-
+  id: 2022
+  type: 7 # label
+  poster_id: 2
+  issue_id: 1 # in repo_id 1
+  label_id: 1
+  content: 0 # remove label
+  created_unix: 946685720
+
+-
+  id: 2023
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  label_id: 1
+  content: 1 # add label
+  created_unix: 946685720
+
+-
+  id: 2024
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  label_id: 2
+  content: 0 # remove label
+  created_unix: 946685720
+
+-
+  id: 2025
+  type: 7 # label
+  poster_id: 2
+  issue_id: 1 # in repo_id 1
+  label_id: 2
+  content: 1 # add label
+  created_unix: 946685820
+
+-
+  id: 2026
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  label_id: 1
+  content: 0 # remove label
+  created_unix: 946685920
+
+-
+  id: 2027
+  type: 7 # label
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  label_id: 2
+  content: 0 # remove label
+  created_unix: 946685920
+
+- id: 2040
+  type: 9 # assignee
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  assignee_id: 1 # self
+  removed_assignee: false # add assignee
+  created_unix: 946688020
+
+- id: 2041
+  type: 9 # assignee
+  poster_id: 2
+  issue_id: 1 # in repo_id 1
+  assignee_id: 1
+  removed_assignee: true # remove assignee
+  created_unix: 946688120
+
+- id: 2042
+  type: 9 # assignee
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  assignee_id: 2
+  removed_assignee: false # add assignee
+  created_unix: 946688220
+
+- id: 2043
+  type: 9 # assignee
+  poster_id: 2
+  issue_id: 1 # in repo_id 1
+  assignee_id: 2 # self
+  removed_assignee: true # remove assignee
+  created_unix: 946688320
+
+- id: 2050
+  type: 23 # lock
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946688420
+
+- id: 2051
+  type: 24 # unlock
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946688520
+
+- id: 2052
+  type: 23 # lock
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  content: "Too heated"
+  created_unix: 946688620
+
+- id: 2053
+  type: 24 # unlock
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946688720
+
+- id: 2060
+  type: 36 # pin
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946688820
+
+- id: 2061
+  type: 37 # unpin
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946688920
+
+- id: 2070
+  type: 2 # close
+  poster_id: 1
+  issue_id: 1 # in repo_id 1
+  created_unix: 946689020
+
+- id: 2071
+  type: 1 # reopen
+  poster_id: 2
+  issue_id: 1 # in repo_id 1
+  created_unix: 946689220
+
+- id: 2072
+  type: 2 # close
+  poster_id: 1
+  issue_id: 2 # pull in repo_id 1
+  created_unix: 946689320
+
+- id: 2073
+  type: 1 # reopen
+  poster_id: 2
+  issue_id: 2 # pull in repo_id 1
+  created_unix: 946689420
+
+- id: 2080
+  type: 3 # issue reference
+  poster_id: 1
+  issue_id: 1 # issue in repo_id 1
+  ref_repo_id: 1
+  ref_issue_id: 5 # issue in repo_id 1
+  created_unix: 946689500
+
+- id: 2081
+  type: 3 # issue reference
+  poster_id: 1
+  issue_id: 1 # issue in repo_id 1
+  ref_repo_id: 1
+  ref_issue_id: 2 # pull in repo_id 1
+  created_unix: 946689600
+
+- id: 2082
+  type: 3 # issue reference
+  poster_id: 1
+  issue_id: 1 # issue in repo_id 1
+  ref_repo_id: 32
+  ref_issue_id: 16 # issue in repo_id 32
+  created_unix: 946689700
+
+- id: 2083
+  type: 3 # issue reference
+  poster_id: 1
+  issue_id: 1 # issue in repo_id 1
+  ref_repo_id: 10
+  ref_issue_id: 8 # pull in repo_id 10
+  created_unix: 946689800
+
+- id: 2090
+  type: 6 # pull reference
+  poster_id: 1
+  issue_id: 2 # pull in repo_id 1
+  ref_repo_id: 1
+  ref_issue_id: 1 # issue in repo_id 1
+  created_unix: 946689900
+
+- id: 2091
+  type: 6 # pull reference
+  poster_id: 1
+  issue_id: 2 # pull in repo_id 1
+  ref_repo_id: 1
+  ref_issue_id: 2 # pull in repo_id 1
+  created_unix: 946690000
+
+- id: 2092
+  type: 6 # pull reference
+  poster_id: 1
+  issue_id: 2 # pull in repo_id 1
+  ref_repo_id: 32
+  ref_issue_id: 16 # issue in repo_id 32
+  created_unix: 946690050
+
+- id: 2093
+  type: 6 # pull reference
+  poster_id: 1
+  issue_id: 2 # pull in repo_id 1
+  ref_repo_id: 10
+  ref_issue_id: 8 # pull in repo_id 10
+  created_unix: 946690100
diff --git a/tests/integration/issue_comment_test.go b/tests/integration/issue_comment_test.go
new file mode 100644
index 0000000000..a09dd7c45e
--- /dev/null
+++ b/tests/integration/issue_comment_test.go
@@ -0,0 +1,311 @@
+// Copyright 2025 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package integration
+
+import (
+	"net/http"
+	"strings"
+	"testing"
+
+	"forgejo.org/tests"
+
+	"github.com/PuerkitoBio/goquery"
+	"github.com/stretchr/testify/assert"
+)
+
+func testIssueCommentChangeEvent(t *testing.T, htmlDoc *HTMLDoc, commentID string, texts, links []string) {
+	event := htmlDoc.Find("#issuecomment-" + commentID + " .text")
+
+	for _, text := range texts {
+		assert.Contains(t, strings.Join(strings.Fields(event.Text()), " "), text)
+	}
+
+	var ids []string
+	var hrefs []string
+	event.Find("a").Each(func(i int, s *goquery.Selection) {
+		if id, exists := s.Attr("id"); exists {
+			ids = append(ids, id)
+		}
+		if href, exists := s.Attr("href"); exists {
+			hrefs = append(hrefs, href)
+		}
+	})
+
+	assert.Equal(t, []string{"event-" + commentID}, ids)
+
+	issueCommentLink := "#issuecomment-" + commentID
+	found := false
+	for _, link := range links {
+		if link == issueCommentLink {
+			found = true
+			break
+		}
+	}
+	if !found {
+		links = append(links, issueCommentLink)
+	}
+	assert.Equal(t, links, hrefs)
+}
+
+func TestIssueCommentChangeMilestone(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Add milestone
+	testIssueCommentChangeEvent(t, htmlDoc, "2000",
+		[]string{"user1 added this to the milestone1 milestone"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/milestone/1"})
+
+	// Modify milestone
+	testIssueCommentChangeEvent(t, htmlDoc, "2001",
+		[]string{"user1 modified the milestone from milestone1 to milestone2"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/milestone/1", "/user2/repo1/milestone/2"})
+
+	// Remove milestone
+	testIssueCommentChangeEvent(t, htmlDoc, "2002",
+		[]string{"user1 removed this from the milestone2 milestone"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/milestone/2"})
+
+	// Deleted milestone
+	testIssueCommentChangeEvent(t, htmlDoc, "2003",
+		[]string{"user1 added this to the (deleted) milestone"},
+		[]string{"/user1"})
+}
+
+func TestIssueCommentChangeProject(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Add project
+	testIssueCommentChangeEvent(t, htmlDoc, "2010",
+		[]string{"user1 added this to the First project project"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/projects/1"})
+
+	// Modify project
+	testIssueCommentChangeEvent(t, htmlDoc, "2011",
+		[]string{"user1 modified the project from First project to second project"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/projects/1", "/user2/repo1/projects/2"})
+
+	// Remove project
+	testIssueCommentChangeEvent(t, htmlDoc, "2012",
+		[]string{"user1 removed this from the second project project"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2/repo1/projects/2"})
+
+	// Deleted project
+	testIssueCommentChangeEvent(t, htmlDoc, "2013",
+		[]string{"user1 added this to the (deleted) project"},
+		[]string{"/user1"})
+}
+
+func TestIssueCommentChangeLabel(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Add multiple labels
+	testIssueCommentChangeEvent(t, htmlDoc, "2020",
+		[]string{"user1 added the label1 label2 labels "},
+		[]string{"/user1", "/user2/repo1/issues?labels=1", "/user2/repo1/issues?labels=2"})
+	assert.Empty(t, htmlDoc.Find("#issuecomment-2021 .text").Text())
+
+	// Remove single label
+	testIssueCommentChangeEvent(t, htmlDoc, "2022",
+		[]string{"user2 removed the label1 label "},
+		[]string{"/user2", "/user2/repo1/issues?labels=1"})
+
+	// Modify labels (add and remove)
+	testIssueCommentChangeEvent(t, htmlDoc, "2023",
+		[]string{"user1 added label1 and removed label2 labels "},
+		[]string{"/user1", "/user2/repo1/issues?labels=1", "/user2/repo1/issues?labels=2"})
+	assert.Empty(t, htmlDoc.Find("#issuecomment-2024 .text").Text())
+
+	// Add single label
+	testIssueCommentChangeEvent(t, htmlDoc, "2025",
+		[]string{"user2 added the label2 label "},
+		[]string{"/user2", "/user2/repo1/issues?labels=2"})
+
+	// Remove multiple labels
+	testIssueCommentChangeEvent(t, htmlDoc, "2026",
+		[]string{"user1 removed the label1 label2 labels "},
+		[]string{"/user1", "/user2/repo1/issues?labels=1", "/user2/repo1/issues?labels=2"})
+	assert.Empty(t, htmlDoc.Find("#issuecomment-2027 .text").Text())
+}
+
+func TestIssueCommentChangeAssignee(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Self-assign
+	testIssueCommentChangeEvent(t, htmlDoc, "2040",
+		[]string{"user1 self-assigned this"},
+		[]string{"/user1"})
+
+	// Remove other
+	testIssueCommentChangeEvent(t, htmlDoc, "2041",
+		[]string{"user1 was unassigned by user2"},
+		[]string{"/user1"})
+	// []string{"/user1", "/user2"})
+
+	// Add other
+	testIssueCommentChangeEvent(t, htmlDoc, "2042",
+		[]string{"user2 was assigned by user1"},
+		[]string{"/user2"})
+	// []string{"/user2", "/user1"})
+
+	// Self-remove
+	testIssueCommentChangeEvent(t, htmlDoc, "2043",
+		[]string{"user2 removed their assignment"},
+		[]string{"/user2"})
+}
+
+func TestIssueCommentChangeLock(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Lock without reason
+	testIssueCommentChangeEvent(t, htmlDoc, "2050",
+		[]string{"user1 locked and limited conversation to collaborators"},
+		[]string{"/user1"})
+
+	// Unlock
+	testIssueCommentChangeEvent(t, htmlDoc, "2051",
+		[]string{"user1 unlocked this conversation"},
+		[]string{"/user1"})
+
+	// Lock with reason
+	testIssueCommentChangeEvent(t, htmlDoc, "2052",
+		[]string{"user1 locked as Too heated and limited conversation to collaborators"},
+		[]string{"/user1"})
+
+	// Unlock
+	testIssueCommentChangeEvent(t, htmlDoc, "2053",
+		[]string{"user1 unlocked this conversation"},
+		[]string{"/user1"})
+}
+
+func TestIssueCommentChangePin(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Pin
+	testIssueCommentChangeEvent(t, htmlDoc, "2060",
+		[]string{"user1 pinned this"},
+		[]string{"/user1"})
+
+	// Unpin
+	testIssueCommentChangeEvent(t, htmlDoc, "2061",
+		[]string{"user1 unpinned this"},
+		[]string{"/user1"})
+}
+
+func TestIssueCommentChangeOpen(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Close issue
+	testIssueCommentChangeEvent(t, htmlDoc, "2070",
+		[]string{"user1 closed this issue"},
+		[]string{"/user1"})
+
+	// Reopen issue
+	testIssueCommentChangeEvent(t, htmlDoc, "2071",
+		[]string{"user2 reopened this issue"},
+		[]string{"/user2"})
+
+	req = NewRequest(t, "GET", "/user2/repo1/pulls/2")
+	resp = MakeRequest(t, req, http.StatusOK)
+	htmlDoc = NewHTMLParser(t, resp.Body)
+
+	// Close pull request
+	testIssueCommentChangeEvent(t, htmlDoc, "2072",
+		[]string{"user1 closed this pull request"},
+		[]string{"/user1"})
+
+	// Reopen pull request
+	testIssueCommentChangeEvent(t, htmlDoc, "2073",
+		[]string{"user2 reopened this pull request"},
+		[]string{"/user2"})
+}
+
+func TestIssueCommentChangeIssueReference(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/issues/1")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Issue reference from issue
+	testIssueCommentChangeEvent(t, htmlDoc, "2080",
+		[]string{"user1 referenced this issue ", "issue5 #4"},
+		[]string{"/user1", "/user2/repo1/issues/4", "#issuecomment-2080", "/user2/repo1/issues/4"})
+
+	// Issue reference from pull
+	testIssueCommentChangeEvent(t, htmlDoc, "2081",
+		[]string{"user1 referenced this issue ", "issue2 #2"},
+		[]string{"/user1", "/user2/repo1/pulls/2", "#issuecomment-2081", "/user2/repo1/pulls/2"})
+
+	// Issue reference from issue in different repo
+	testIssueCommentChangeEvent(t, htmlDoc, "2082",
+		[]string{"user1 referenced this issue from org3/repo21", "just a normal issue #1"},
+		[]string{"/user1", "/org3/repo21/issues/1", "#issuecomment-2082", "/org3/repo21/issues/1"})
+
+	// Issue reference from pull in different repo
+	testIssueCommentChangeEvent(t, htmlDoc, "2083",
+		[]string{"user1 referenced this issue from user12/repo10 ", "pr2 #1"},
+		[]string{"/user1", "/user12/repo10/pulls/1", "#issuecomment-2083", "/user12/repo10/pulls/1"})
+}
+
+func TestIssueCommentChangePullReference(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	req := NewRequest(t, "GET", "/user2/repo1/pulls/2")
+	resp := MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	// Pull reference from issue
+	testIssueCommentChangeEvent(t, htmlDoc, "2090",
+		[]string{"user1 referenced this pull request ", "issue1 #1"},
+		[]string{"/user1", "/user2/repo1/issues/1", "#issuecomment-2090", "/user2/repo1/issues/1"})
+
+	// Pull reference from pull
+	testIssueCommentChangeEvent(t, htmlDoc, "2091",
+		[]string{"user1 referenced this pull request ", "issue2 #2"},
+		[]string{"/user1", "/user2/repo1/pulls/2", "#issuecomment-2091", "/user2/repo1/pulls/2"})
+
+	// Pull reference from issue in different repo
+	testIssueCommentChangeEvent(t, htmlDoc, "2092",
+		[]string{"user1 referenced this pull request from org3/repo21", "just a normal issue #1"},
+		[]string{"/user1", "/org3/repo21/issues/1", "#issuecomment-2092", "/org3/repo21/issues/1"})
+
+	// Pull reference from pull in different repo
+	testIssueCommentChangeEvent(t, htmlDoc, "2093",
+		[]string{"user1 referenced this pull request from user12/repo10 ", "pr2 #1"},
+		[]string{"/user1", "/user12/repo10/pulls/1", "#issuecomment-2093", "/user12/repo10/pulls/1"})
+}