Hi,
From location /var/sam/www/webtop/public/images/my/ copy via scp to your computer file header-transient.png edit it with paint (make it white) name it header-white.png upload it to the same location. Then you have to make modification in apm_full.css so you need to access
Advanced Customization I'have version 13.1.1 so path is Access ›› Profiles / Policies >> Customization >> Advanced select from tree your profile click the apm_full.css find in the code text header-transient.png and replace with header-transient.png