Currently, in the Page Builder in edit mode, when the first block of the Landing Page is located at the top of the page (meaning that there is no header or any other field displayed there), then this block's toolbar is hidden under the top menu.

Steps to reproduce:

1. Create a new eZ Platform EE installation.
2. Add the following configuration to app/config/ezplatform.yml:
   Unable to find source-code formatter for language: yml. Available languages are: actionscript, ada, applescript, bash, c, c#, c++, cpp, css, erlang, go, groovy, haskell, html, java, javascript, js, json, lua, none, nyan, objc, perl, php, python, r, rainbow, ruby, scala, sh, sql, swift, visualbasic, xml, yaml

   ezpublish:
       system:
           site_group:
               content_view:
                   full:
                       landing_page:
                           template: 'full/landing_page.html.twig'
                           match:
                               Identifier\ContentType: 'landing_page'
   

3. Create file app/Resources/views/full/landing_page.html.twig with the following content:
   Unable to find source-code formatter for language: twig. Available languages are: actionscript, ada, applescript, bash, c, c#, c++, cpp, css, erlang, go, groovy, haskell, html, java, javascript, js, json, lua, none, nyan, objc, perl, php, python, r, rainbow, ruby, scala, sh, sql, swift, visualbasic, xml, yaml

   {% extends noLayout == true ? viewbaseLayout : pagelayout %}
   {% block content %}
       {{ ez_render_field(content, 'page') }}
   {% endblock %}
   

4. In Admin UI, navigate to "Page" tab and enter the edit mode for the Home content. Notice that the toolbar for the first block is hidden. It should show when you hover over the block.