Magento 2.0 and 2.1 layout issue

Question

In my default.xml I have

<referenceContainer name="header.container">
 <block name="tonysamperi_developertools.all" 
 class="TonySamperi\DeveloperTools\Block\All" 
 before="-" 
 template="TonySamperi_DeveloperTools::html/all.phtml" />
</referenceContainer>

In Magento 2.1 I have my extension on the very top of the page, before the panel header. (Correct behaviour)

In Magento 2.0 My extension and the panel header are swapped!

Anyone who may know why??

Answer 1

I found out that the before attribute can be filled with a container

<referenceContainer name="header.container">
 <block name="tonysamperi_developertools.all" 
 class="TonySamperi\DeveloperTools\Block\All" 
 before="header.panel.wrapper" 
 template="TonySamperi_DeveloperTools::html/all.phtml" />
</referenceContainer>