till we process this issue, you can manually upload images within their website https://nostr.build then copy/paste the URL to your board.

nostr:nprofile1qqsglv2qkn5dmmuhee9cy8fywfu2rfp4xd3xy0myqg2gfvmjl9yqqrqpr3mhxue69uhkummnw3ezucnfw33k76twv4ezuum0vd5kzmqpr9mhxue69uhhyetvv9ujumn0wd68yanfv4mjucm0d5q3samnwvaz7tmsw43xc6tr9eex2mrp095kueewd9hsfz6x6a wen free nostr.build API for Pinstr? 👀