Magic heading default settings in 5.5.1Browser Info Environment
When creating a Magic Heading block, Magic Heading will detect which version of C5 is in use and adjust the 'exclude before' and 'exclude any' selectors for Plain Yogurt or Greek Yogurt accordingly.
However, if you update a 5.4 site to 5.5.x and update the theme, you will need to adjust the Magic Heading settings, just as you may need to for any other theme change.
for 5.5.1 Greek Yogurt:
Exclude before: #main-content-container
Exclude Any: #right-sidebar-container, #left-sidebar-container