The www/ subdirectory defines what the web server can access. The Compose configuration, the Dockerfile, notes and working copies can stay in the project directory outside it.
When the server sees the whole directory, every new file may need its own blocking rule. With a separate public directory, you choose what the server serves.
The change applies to templates for new projects. Older projects keep their layout, and the panel does not rebuild their Compose configuration automatically.
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