Move `js-*` class to fix E2E spec

`.js-epic-container` was being added to multiple elements which was
causing JS errors

ee/app/assets/javascripts/epic/epic_tabs.js

@@ -5,7 +5,7 @@ import { parseBoolean } from '~/lib/utils/common_utils';
 export default class EpicTabs {
   constructor() {
     this.epicTreesEnabled = gon.features && gon.features.epicTrees;
-    this.wrapper = document.querySelector('.js-epic-container:not(.breadcrumbs)');
+    this.wrapper = document.querySelector('.js-epic-container');
     this.epicTabs = this.wrapper.querySelector('.js-epic-tabs-container');
     this.discussionFilterContainer = this.epicTabs.querySelector('.js-discussion-filter-container');
     const allowSubEpics = parseBoolean(this.epicTabs.dataset.allowSubEpics);

ee/app/views/groups/epics/show.html.haml

 - @no_breadcrumb_container = false
-- @no_container = false
-- @content_class = "js-epic-container #{'limit-container-width' unless fluid_layout}"
+- @no_container = true
+- @content_class = 'limit-container-width' unless fluid_layout
 
 - epic_reference = @epic.to_reference
 - sub_epics_feature_available = @group.feature_available?(:subepics)
@@ -23,10 +23,11 @@
 - add_page_startup_graphql_call('epic/epic_details', { fullPath: @group.full_path, iid: @epic.iid })
 - add_page_startup_graphql_call('epic/epic_children', { fullPath: @group.full_path, iid: @epic.iid, pageSize: 100, epicEndCursor: '', issueEndCursor: '' })
 
-#epic-app-root{ data: epic_show_app_data(@epic),
+%div{ class: ['js-epic-container', container_class, @content_class] }
+  #epic-app-root{ data: epic_show_app_data(@epic),
     'data-allow-sub-epics' => allow_sub_epics }
 
-.epic-tabs-holder
+  .epic-tabs-holder
     .epic-tabs-container.js-epic-tabs-container{ data: { allow_sub_epics: allow_sub_epics } }
       %ul.epic-tabs.nav-tabs.nav.nav-links.scrolling-tabs
         %li.tree-tab
@@ -40,7 +41,7 @@
             %a#roadmap-tab{ href: '#roadmap', data: { toggle: 'tab' } }
               = _('Roadmap')
 
-.tab-content.epic-tabs-content.js-epic-tabs-content
+  .tab-content.epic-tabs-content.js-epic-tabs-content
     #tree.tab-pane.show.active
       .row
         %section.col-md-12
@@ -71,14 +72,14 @@
               sorted_by: roadmap_sort_order,
               inner_height: '600',
               child_epics: 'true' } }
-%hr.epic-discussion-separator.mt-1.mb-0
-.d-flex.justify-content-between.content-block.content-block-small.emoji-list-container.js-noteable-awards
+  %hr.epic-discussion-separator.mt-1.mb-0
+  .d-flex.justify-content-between.content-block.content-block-small.emoji-list-container.js-noteable-awards
     = render 'award_emoji/awards_block', awardable: @epic, inline: true
     .d-flex.flex-wrap.align-items-center.justify-content-lg-end
       #js-vue-sort-issue-discussions
       #js-vue-discussion-filter{ data: { default_filter: current_user&.notes_filter_for(@epic),
         notes_filters: UserPreference.notes_filters.to_json } }
-.row
+  .row
     %section.col-md-12
       %script.js-notes-data{ type: "application/json" }= initial_notes_data(true).to_json.html_safe
       .issuable-discussion

ee/changelogs/unreleased/283932-flaky-test-qa-specs-features-ee-browser_ui-2_plan-epic-epics_ma.yml

+---
+title: Fix Epic tabs when open registration alert is visible
+merge_request: 49150
+author:
+type: fixed

qa/qa/specs/features/ee/browser_ui/2_plan/epic/epics_management_spec.rb

@@ -36,7 +36,7 @@ module QA
             epic.visit!
           end
 
-          it 'adds/removes issue to/from epic', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/issues/526', quarantine: { issue: 'https://gitlab.com/gitlab-org/gitlab/-/issues/283932', type: :investigating } do
+          it 'adds/removes issue to/from epic', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/issues/526' do
             EE::Page::Group::Epic::Show.perform do |show|
               show.add_issue_to_epic(issue.web_url)