Installing when registry.docker.com is not available: using registry-mirror in docker daemon config

[syn]

When running a normal ./cloudron-setup in a restricted network environment or during a docker hub outage:

2026-06-21T09:58:41 ==> installer: downloading new addon images
2026-06-21T09:58:41 ==> installer:      Pulling docker images: registry.docker.com/cloudron/graphite:3.5.3@sha256:44ddbfd8c30d3eaa4fa6db207f4e18a4f1749ce6ed82d44e9e9a233a96febced registry.docker.com/cloudron/mail:3.18.2@sha256:130d518db6d56aa536f19a4901d7bc265666927165205aed302e6450c51791c7 registry.docker.com/cloudron/mongodb:6.3.0@sha256:8757111970a99fb9a9880f02a2a77fe9cb7368745fcff555bf528471ecb50ec3 registry.docker.com/cloudron/mysql:3.6.0@sha256:12fd9d8d92a41b78ca422ef05d7dade75eba4f8647b0fabaa873ba6efb607783 registry.docker.com/cloudron/postgresql:6.4.0@sha256:759c5c68e8f3a91592911177dcd2e9e39de48528b7b1bab659bae2f5ebd2d207 registry.docker.com/cloudron/redis:3.8.0@sha256:54a12252edbc326fd4d10e8c00836cc68776f3463f22366279f7cd8d4dafd20f registry.docker.com/cloudron/sftp:3.10.0@sha256:c3a65928ef5cf7ba0750e93d9c605fb39e7fec02de7db05cffe80927b39943de registry.docker.com/cloudron/turn:1.8.2@sha256:9f3609969a5757837505c584c98246a3035a84a273b9be491665ac026423fd5f
Error response from daemon: Get "https://registry.ipv4.docker.com/v2/": net/http: TLS handshake timeout

I configured the mirror via /etc/docker/daemon.json with e.g {"registry-mirrors": ["https://mirror.gcr.io"]}

But currently cloudron uses registry.docker.com as an explicit registry host, so it bypasses the Docker Hub mirror registry config.

Patching src/infra_version.js to replace registry.docker.com with docker.io enables the proxying.

The ipv6 workaround implemented in or after https://forum.cloudron.io/topic/7420/ipv6-only-cloudron would also need to be patched, but otherwise this seems a net win?