After updating cli to latest version and running up all of my compose containers', volumes', networks' prefixes changed from devcontainer_devcontainer_ (due to folder being ./devcontainer) to just devcontainer_. I don't have COMPOSE_PROJECT_NAME set anywhere. I setup devcontainer with
npx devcontainer --workspace-folder=. up ran from Makefile so working dir should be always the same. The only change I'm sure I did was to update cli 0.56 -> 0.60, rollback doesn't help. I think the --project-name disappeared from echo/logs, but I'm not certain.