diff --git a/changelogs/unreleased/63417-add-missing-class.yml b/changelogs/unreleased/63417-add-missing-class.yml
new file mode 100644
index 0000000000000000000000000000000000000000..3030f5c57e43e6b9344674a6f87b8ceeb0984a63
--- /dev/null
+++ b/changelogs/unreleased/63417-add-missing-class.yml
@@ -0,0 +1,5 @@
+---
+title: Indent collapsible sections
+merge_request: 29804
+author:
+type: other
diff --git a/lib/gitlab/ci/ansi2html.rb b/lib/gitlab/ci/ansi2html.rb
index 6109b45ffd2f364f43ebf36e2a5245cec55f6fe2..fc3223e7442ed1a5e4603e107a02a9a1b7b89b41 100644
--- a/lib/gitlab/ci/ansi2html.rb
+++ b/lib/gitlab/ci/ansi2html.rb
@@ -310,7 +310,7 @@ module Gitlab
if @sections.any?
css_classes << "section"
- css_classes << "js-section-header" if @lineno_in_section == 0
+ css_classes << "js-section-header section-header" if @lineno_in_section == 0
css_classes += sections.map { |section| "js-s-#{section}" }
end
diff --git a/spec/lib/gitlab/ci/ansi2html_spec.rb b/spec/lib/gitlab/ci/ansi2html_spec.rb
index ac4612dda925bd99bdca07797293b6c04c1d5541..3d57ce431ab81016b93ca18cafc45c0ef24f9b58 100644
--- a/spec/lib/gitlab/ci/ansi2html_spec.rb
+++ b/spec/lib/gitlab/ci/ansi2html_spec.rb
@@ -231,8 +231,8 @@ describe Gitlab::Ci::Ansi2html do
it 'prints light red' do
text = "#{section_start}\e[91mHello\e[0m\n#{section_end}"
- header = %{}
- line_break = %{}
+ header = %{}
+ line_break = %{}
line = %{}
empty_line = %{}
html = "#{section_start_html}#{header}#{line_break}#{line}#{empty_line}#{section_end_html}"