diff --git a/app/helpers/blob_helper.rb b/app/helpers/blob_helper.rb
index 06beeebe2ba..3e1bb9af5cc 100644
--- a/app/helpers/blob_helper.rb
+++ b/app/helpers/blob_helper.rb
@@ -37,7 +37,7 @@ module BlobHelper
   end
 
   def ide_edit_button(project = @project, ref = @ref, path = @path, options = {})
-    return unless Feature.enabled?(:web_ide_default)
+    return if Feature.enabled?(:web_ide_default)
     return unless blob = readable_blob(options, path, project, ref)
 
     edit_button_tag(blob,
diff --git a/app/serializers/diff_file_base_entity.rb b/app/serializers/diff_file_base_entity.rb
index ede9e04b722..d8630165e49 100644
--- a/app/serializers/diff_file_base_entity.rb
+++ b/app/serializers/diff_file_base_entity.rb
@@ -27,9 +27,13 @@ class DiffFileBaseEntity < Grape::Entity
 
     next unless merge_request.source_project
 
-    project_edit_blob_path(merge_request.source_project,
-      tree_join(merge_request.source_branch, diff_file.new_path),
-      options)
+    if Feature.enabled?(:web_ide_default)
+      ide_edit_path(merge_request.source_project, merge_request.source_branch, diff_file.new_path)
+    else
+      project_edit_blob_path(merge_request.source_project,
+        tree_join(merge_request.source_branch, diff_file.new_path),
+        options)
+    end
   end
 
   expose :old_path_html do |diff_file|
diff --git a/spec/features/merge_request/maintainer_edits_fork_spec.rb b/spec/features/merge_request/maintainer_edits_fork_spec.rb
index 7839b97122c..aead98dae23 100644
--- a/spec/features/merge_request/maintainer_edits_fork_spec.rb
+++ b/spec/features/merge_request/maintainer_edits_fork_spec.rb
@@ -18,6 +18,8 @@ describe 'a maintainer edits files on a source-branch of an MR from a fork', :js
   end
 
   before do
+    stub_feature_flags(web_ide_default: false)
+
     target_project.add_maintainer(user)
     sign_in(user)