The vertical tabs coming after the Version plugin didn't show up. After some investigation I discovered the tabs for Local tasks, content and block, were wrapped in the the Version plugin details container.
This is caused by the use of a non-existing #postfix attribute on the environments wrapper.
$elements['environments'] = [
'#type' => 'details',
'#open' => (bool) $triggering_element,
'#title' => $this->t('Environments'),
'#prefix' => '<div id="navigation-extra-version-environments-wrapper">',
'#postfix' => '</div>',
];
After fixing this, the vertical tabs of hidden plugins show as expected.
$elements['environments'] = [
'#type' => 'details',
'#open' => (bool) $triggering_element,
'#title' => $this->t('Environments'),
'#prefix' => '<div id="navigation-extra-version-environments-wrapper">',
'#suffix' => '</div>',
];
Active
1.0
Code
Issue #3512449: Vertical tabs coming after Version plugin in...