Lazy Loading and Missing Images
If you see missing images on the checkout page, order pay page, or thank you page it most likely means that you have enabled your theme's Lazy Loading functionality.
We do this to increase performance reduce compatibility conflicts.
How To Fix Missing Images
To fix missing images on the checkout page, you should disable your theme's lazy loading functionality.
WordPress Core added native lazy loading in 5.5. This leverages the loading=lazy attribute supported by most major browser, including Chrome and Firefox.
CheckoutWC supports this functionality and most themes properly allow WordPress lazy loading if you disable their lazy loading functionality.
The only downsides of native lazy loading is that it isn't currently supported by Safari. But support is expected soon.
And as of WordPress 5.7, support for lazy loading iframes is also enabled!
If You Really Really Need Safari Support
If lazy loading in Safari is crucial for your use case, we recommend using a lazy load plugin in favor of using your theme's lazy loading functionality. This will bypass any theme restrictions in CheckoutWC.