Having the same issue! Hoping you get an answer.
Topic summary
404 (Not Found) errors when loading images in a custom Shopify header built from scratch. Images sourced from section settings (logo_desktop/logo_mobile via image_picker) and even product.featured_image fail to load.
Code snippet is central: Liquid template renders logos using image_url with widths from settings, and includes a schema defining image_picker fields for desktop and mobile. The browser developer log shows 404s for the image requests.
The author suspects this may relate to using a development store but provides no confirmation or error URLs. Another participant reports having the same issue.
No fix or consensus is provided in-thread. The original poster offers offline help via email. Status: unresolved; key questions remain about whether the problem is environment-related or due to how image URLs are generated.