If you have configured https website and see SSL validation error (no green padlock) because of logo file (usually white logo) you need to perform this actions:
- Make sure you have valid SSL certificate installed (ask hosting support for help with this)
- Make sure you have Force SSL or similar plugin installed
- Go to Appearance > Theme settings > Logo and scroll down to see Logo for Transparent Header (Light logo) option. Upload your light logo version here (or remove sample logo loaded with demo data).