File upload with filemanager not working on settings pages with behat

I believe the problem is in the behat_theme_boost_behat_repository_upload->get_filepicker_node().

Conditions for the test to fail:

• the filemanager needs to be on a settings.php
• using a theme based on boost, basically using the behat_theme_boost_behat_repository_upload->get_filepicker_node()

Basically the 

//input[./@id = //label[normalize-space(.)=$filepickerelement]/@for]" .

"//ancestor::div[contains(concat(' ', normalize-space(@class), ' '), ' felement ')]

xpath will find nothing because there is no "felement" class on the wrapper div when a filemanager is on a settings.php.

So reproduction steps are:

• in config.php set $CFG->theme = 'boost';
• in a .feature file: 

@javascript

Scenario: configstoredfile test

  When I log in as "admin"

  Then I navigate to "Appearance > Logos" in site administration

  And I upload "xyz test file" file to "Logo" filemanager

 This should end with:

"Logo" filepicker can not be found (Behat\Mink\Exception\ExpectationException)

I think moodle currently does not have any test for file upload located on a settings.php (at least I did not find any), probably thats why nobody run into this. OR I seriously overlooked something, thats also a possibility, in that case please enlighten me.