I hear a lot of people complaining about how this is apples fault but it is not it is disabled for a good reason page speed of websites. When you make a website you want your end users to to see your website as fast as possible but if you use your background-attachment fixed you make that container re-render the image every time you scroll because of this mobile devices deactivate this feature on all devices. think about your end users when making a website.
Callmenv
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