diff --git a/app/controllers/projects/compare_controller.rb b/app/controllers/projects/compare_controller.rb
index 57725944d68..af0b69a2442 100644
--- a/app/controllers/projects/compare_controller.rb
+++ b/app/controllers/projects/compare_controller.rb
@@ -24,7 +24,6 @@ class Projects::CompareController < Projects::ApplicationController
       @diff_refs = [@base_commit, @commit]
       @diff_notes_disabled = true
       @grouped_diff_notes = {}
-      @comments_target = {}
     end
   end
 
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 99630bc1099..dd86b940a08 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -138,7 +138,6 @@ class Projects::MergeRequestsController < Projects::ApplicationController
     @base_commit = @merge_request.diff_base_commit
     @diffs = @merge_request.compare.diffs(diff_options) if @merge_request.compare
     @diff_notes_disabled = true
-    @comments_target = {}
 
     @pipeline = @merge_request.pipeline
     @statuses = @pipeline.statuses if @pipeline
diff --git a/app/helpers/notes_helper.rb b/app/helpers/notes_helper.rb
index 42419aa908e..e1c8152885a 100644
--- a/app/helpers/notes_helper.rb
+++ b/app/helpers/notes_helper.rb
@@ -24,6 +24,27 @@ module NotesHelper
     }.to_json
   end
 
+  def note_text_file_data
+    return {} unless defined?(@comments_target) && @comments_target.any?
+
+    @comments_target.slice(:noteable_id, :noteable_type, :commit_id).merge(note_type: LegacyDiffNote.name)
+  end
+
+  def note_line_parallel_data(line_code, line_type)
+    data = {
+      line_code: line_code,
+      line_type: line_type,
+    }
+
+    unless @diff_notes_disabled
+      data.merge!(
+        discussion_id: discussion_id(line_code)
+      )
+    end
+
+    data
+  end
+
   def discussion_id(line_code)
     LegacyDiffNote.build_discussion_id(
       @comments_target[:noteable_type],
diff --git a/app/mailers/emails/projects.rb b/app/mailers/emails/projects.rb
index 1a6900b3293..e0af7081411 100644
--- a/app/mailers/emails/projects.rb
+++ b/app/mailers/emails/projects.rb
@@ -30,7 +30,6 @@ module Emails
       @target_url = @message.target_url
       @project = Project.find(project_id)
       @diff_notes_disabled = true
-      @comments_target = {}
 
       add_project_headers
       headers['X-GitLab-Author'] = @message.author_username
diff --git a/app/views/projects/diffs/_line.html.haml b/app/views/projects/diffs/_line.html.haml
index da1c81bfc15..1953720b79e 100644
--- a/app/views/projects/diffs/_line.html.haml
+++ b/app/views/projects/diffs/_line.html.haml
@@ -1,5 +1,5 @@
 - type = line.type
-- line_data = @comments_target.any? ? { data: { discussion_id: discussion_id(line_code) } } : {}
+- line_data = @diff_notes_disabled ? {} : { data: { discussion_id: discussion_id(line_code) } }
 %tr.line_holder{ line_data, id: line_code, class: type }
   - case type
   - when 'match'
@@ -15,11 +15,11 @@
       - if defined?(plain) && plain
         = link_text
       - else
-        %a{href: "##{line_code}", data: { linenumber: link_text }}= "  "
+        %a{href: "##{line_code}", data: { linenumber: link_text }}
     %td.new_line.diff-line-num{ class: type, data: { linenumber: line.new_pos } }
       - link_text = type == "old" ? " " : line.new_pos
       - if defined?(plain) && plain
         = link_text
       - else
-        %a{href: "##{line_code}", data: { linenumber: link_text }}= ""
+        %a{href: "##{line_code}", data: { linenumber: link_text }}
     %td.line_content{ class: ['noteable_line', type], data: { line_code: line_code, line_type: type } }= diff_line_content(line.text, type)
diff --git a/app/views/projects/diffs/_parallel_view.html.haml b/app/views/projects/diffs/_parallel_view.html.haml
index e205686ceea..a234f778190 100644
--- a/app/views/projects/diffs/_parallel_view.html.haml
+++ b/app/views/projects/diffs/_parallel_view.html.haml
@@ -1,6 +1,5 @@
 / Side-by-side diff view
-- text_file_data = @comments_target.any? ? { data: { noteable_id: @comments_target[:noteable_id], noteable_type: @comments_target[:noteable_type], commit_id: @comments_target[:commit_id], note_type: LegacyDiffNote.name } } : {}
-%div.text-file.diff-wrap-lines.code.file-content.js-syntax-highlight{ text_file_data }
+%div.text-file.diff-wrap-lines.code.file-content.js-syntax-highlight{ data: note_text_file_data }
   %table
     - diff_file.parallel_diff_lines.each do |line|
       - left = line[:left]
@@ -14,9 +13,9 @@
           %td.new_line.diff-line-num.empty-cell
           %td.line_content.parallel.match= left[:text]
         - else
-          %td.old_line.diff-line-num{id: left[:line_code], class: "#{left[:type]} #{'empty-cell' if !left[:number]}", data: { linenumber: left[:number] }}
+          %td.old_line.diff-line-num{id: left[:line_code], class: "#{left[:type]} #{'empty-cell' unless left[:number]}", data: { linenumber: left[:number] }}
             %a{href: "##{left[:line_code]}" }= raw(left[:number])
-          %td.line_content{class: "parallel noteable_line #{left[:type]} #{'empty-cell' if left[:text].empty?}", data: { discussion_id: discussion_id(left[:line_code]), line_type: left[:type], line_code: left[:line_code] }}= diff_line_content(left[:text])
+          %td.line_content{class: "parallel noteable_line #{left[:type]} #{'empty-cell' if left[:text].empty?}", data: note_line_parallel_data(left[:line_code], left[:type]) }= diff_line_content(left[:text])
 
           - if right[:type] == 'new'
             - new_line_class = 'new'
@@ -25,9 +24,9 @@
             - new_line_class = nil
             - new_line_code = left[:line_code]
 
-          %td.new_line.diff-line-num{id: new_line_code, class: "#{new_line_class} #{'empty-cell' if !right[:number]}", data: { linenumber: right[:number] } }
+          %td.new_line.diff-line-num{id: new_line_code, class: "#{new_line_class} #{'empty-cell' unless right[:number]}", data: { linenumber: right[:number] } }
             %a{href: "##{new_line_code}" }= raw(right[:number])
-          %td.line_content.parallel{class: "noteable_line #{new_line_class} #{'empty-cell' if right[:text].empty?}", data: { discussion_id: discussion_id(new_line_code), line_type: new_line_class, line_code: new_line_code }}= diff_line_content(right[:text])
+          %td.line_content.parallel{class: "noteable_line #{new_line_class} #{'empty-cell' if right[:text].empty?}", data: note_line_parallel_data(new_line_code, new_line_class) }= diff_line_content(right[:text])
 
       - unless @diff_notes_disabled
         - notes_left, notes_right = organize_comments(left, right)
diff --git a/app/views/projects/diffs/_text_file.html.haml b/app/views/projects/diffs/_text_file.html.haml
index a1c3bf74b0a..3a3aff4d054 100644
--- a/app/views/projects/diffs/_text_file.html.haml
+++ b/app/views/projects/diffs/_text_file.html.haml
@@ -3,8 +3,7 @@
   .suppressed-container
     %a.show-suppressed-diff.js-show-suppressed-diff Changes suppressed. Click to show.
 
-- text_file_data = @comments_target.any? ? { data: { noteable_id: @comments_target[:noteable_id], noteable_type: @comments_target[:noteable_type], commit_id: @comments_target[:commit_id], note_type: LegacyDiffNote.name } } : {}
-%table.text-file.code.js-syntax-highlight{ text_file_data, class: too_big ? 'hide' : '' }
+%table.text-file.code.js-syntax-highlight{ data: note_text_file_data, class: too_big ? 'hide' : '' }
 
   - last_line = 0
   - diff_file.highlighted_diff_lines.each_with_index do |line, index|