same issue here.
“not a valid header”
divi theme
plugins
css hero
divi booster
divi module editor
duplicator
elegant themes updater
force regenerate thumbnails
google analytics dashboard for wp
google seo pressor snippet plugin
jetpack
microthemer
polylang
timeline express pro
updraftplus
w3 total cache
wonderplugin carousel
wordpress importer
wordpress seo
wp smush
