diff --git a/templates/repo/diff/section_split.tmpl b/templates/repo/diff/section_split.tmpl
index 7b1f72939e..50522d989e 100644
--- a/templates/repo/diff/section_split.tmpl
+++ b/templates/repo/diff/section_split.tmpl
@@ -1,4 +1,5 @@
 {{$file := .file}}
+{{$blobExcerptRepoLink := or $.root.CommitRepoLink $.root.RepoLink}}
 <colgroup>
 	<col width="50">
 	<col width="10">
@@ -18,17 +19,17 @@
 					<td class="lines-num lines-num-old">
 						<div class="tw-flex">
 						{{if or (eq $line.GetExpandDirection 3) (eq $line.GetExpandDirection 5)}}
-							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=down&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=down&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 								{{svg "octicon-fold-down"}}
 							</button>
 						{{end}}
 						{{if or (eq $line.GetExpandDirection 3) (eq $line.GetExpandDirection 4)}}
-							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=up&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=up&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 								{{svg "octicon-fold-up"}}
 							</button>
 						{{end}}
 						{{if eq $line.GetExpandDirection 2}}
-							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+							<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=split&direction=&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 								{{svg "octicon-fold"}}
 							</button>
 						{{end}}
diff --git a/templates/repo/diff/section_unified.tmpl b/templates/repo/diff/section_unified.tmpl
index d7fe75895b..ab78097f26 100644
--- a/templates/repo/diff/section_unified.tmpl
+++ b/templates/repo/diff/section_unified.tmpl
@@ -1,4 +1,5 @@
 {{$file := .file}}
+{{$blobExcerptRepoLink := or $.root.CommitRepoLink $.root.RepoLink}}
 <colgroup>
 	<col width="50">
 	<col width="50">
@@ -14,17 +15,17 @@
 					<td colspan="2" class="lines-num">
 						<div class="tw-flex">
 							{{if or (eq $line.GetExpandDirection 3) (eq $line.GetExpandDirection 5)}}
-								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=down&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=down&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 									{{svg "octicon-fold-down"}}
 								</button>
 							{{end}}
 							{{if or (eq $line.GetExpandDirection 3) (eq $line.GetExpandDirection 4)}}
-								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=up&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=up&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 									{{svg "octicon-fold-up"}}
 								</button>
 							{{end}}
 							{{if eq $line.GetExpandDirection 2}}
-								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$.root.CommitRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
+								<button class="code-expander-button" hx-target="closest tr" hx-get="{{$blobExcerptRepoLink}}/blob_excerpt/{{PathEscape $.root.AfterCommitID}}?{{$line.GetBlobExcerptQuery}}&style=unified&direction=&wiki={{$.root.PageIsWiki}}&anchor=diff-{{$file.NameHash}}K{{$line.SectionInfo.RightIdx}}">
 									{{svg "octicon-fold"}}
 								</button>
 							{{end}}
diff --git a/tests/integration/compare_test.go b/tests/integration/compare_test.go
index ffcdd2f23d..5d585e061d 100644
--- a/tests/integration/compare_test.go
+++ b/tests/integration/compare_test.go
@@ -18,6 +18,7 @@ import (
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/optional"
+	"code.gitea.io/gitea/modules/test"
 	repo_service "code.gitea.io/gitea/services/repository"
 	files_service "code.gitea.io/gitea/services/repository/files"
 	"code.gitea.io/gitea/tests"
@@ -251,8 +252,41 @@ func TestCompareCodeExpand(t *testing.T) {
 				owner.Name, repo.Name, forker.Name, repo.Name+"-copy")
 			resp := session.MakeRequest(t, req, http.StatusOK)
 			htmlDoc := NewHTMLParser(t, resp.Body)
-			htmlDoc.AssertElement(t, fmt.Sprintf("button.code-expander-button[hx-get^='/%s/%s/blob_excerpt/'] svg.octicon-fold-up", forker.Name, repo.Name+"-copy"), true)
-			htmlDoc.AssertElement(t, fmt.Sprintf("button.code-expander-button[hx-get^='/%s/%s/blob_excerpt/'] svg.octicon-fold-down", forker.Name, repo.Name+"-copy"), true)
+
+			els := htmlDoc.Find(`button.code-expander-button[hx-get]`)
+
+			// all the links in the comparison should be to the forked repo&branch
+			assert.NotZero(t, els.Length())
+			expectedPrefix := fmt.Sprintf("/%s/%s/blob_excerpt/", forker.Name, repo.Name+"-copy")
+			for i := 0; i < els.Length(); i++ {
+				link := els.Eq(i).AttrOr("hx-get", "")
+				assert.True(t, strings.HasPrefix(link, expectedPrefix))
+			}
+		})
+
+		t.Run("code expander targets the repo in a PR", func(t *testing.T) {
+			defer tests.PrintCurrentTest(t)()
+
+			// Create a pullrequest
+			resp := testPullCreate(t, session, forker.Name, repo.Name+"-copy", false, "main", "code-expand", "This is a pull title")
+
+			// Grab the URL for the PR
+			url := test.RedirectURL(resp) + "/files"
+
+			// Visit the PR's diff
+			req := NewRequest(t, "GET", url)
+			resp = session.MakeRequest(t, req, http.StatusOK)
+			htmlDoc := NewHTMLParser(t, resp.Body)
+
+			els := htmlDoc.Find(`button.code-expander-button[hx-get]`)
+
+			// all the links in the comparison should be to the original repo&branch
+			assert.NotZero(t, els.Length())
+			expectedPrefix := fmt.Sprintf("/%s/%s/blob_excerpt/", owner.Name, repo.Name)
+			for i := 0; i < els.Length(); i++ {
+				link := els.Eq(i).AttrOr("hx-get", "")
+				assert.True(t, strings.HasPrefix(link, expectedPrefix))
+			}
 		})
 	})
 }