feat: stop the card flashing in eventCard

[Sboonny]

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Without onError the eventCards will fallback to the image, while we need it to fallback if there is no image

[ghost]

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Legend

[Sboonny]

rec-tab.webm

The issue is the fallback is shown while the image is lazy loading

[Sboonny]

Did you remember the image falling gracefully discussion in discord, and made suggestion based on it? 🤣

I have forgot about it completely, edit: well to be honest misremembered it, and didn't test it. 🤦 Thank you 💚

[gikf]

Thanks, this makes sense. The fallbackSrc and fallbackStrategy still might be useful though, for cases when image_url is provided, but cannot be loaded.