It’s a shared nostr event that other apps can use to refer to your blossom servers list. Currently yours is empty so you need to set it first so in the case where a media cannot load, we just use it...
Also, usually the uploaded media have its fallback url in case the first one did not work. The original note had the fallback url but it did not appear on your side, I think we have some sort of issue on our end 🤔
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