All clients that relied on the mainnet Hiro API were impacted. This includes the Explorer, Stacks desktop and web wallets, the stacks CLI, and others. Requests on all endpoints to the mainnet API were still being served, but may have received outdated data.
The mainnet Stacks Blockchain API instances serving traffic were experiencing connection issues to the Stacks Blockchain nodes it depended upon. We believe this issue is related, and it’s being investigated right now.