Add docker-compose instructions for ARM64 (#5175)

* Add docker-compose instructions for ARM64

* Update Docker/README.md

* Update Docker/README.md

---------

Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>

Docker/README.md

@@ -256,7 +256,7 @@ sudo nano /var/lib/docker/volumes/freshrss_data/_data/config.php
 
 ## Docker Compose
 
-First, put variables such as passwords in your `.env` file (see [`example.env`](./freshrss/example.env)):
+First, put variables such as passwords in your `.env` file, which can live where your `docker-compose.yml` should be. See [`example.env`](./freshrss/example.env).
 
 ```ini
 ADMIN_EMAIL=admin@example.net
@@ -381,6 +381,27 @@ docker-compose down --remove-orphans --volumes
 
 > ℹ️ You can combine it with `-f docker-compose-db.yml` to spin a PostgreSQL database.
 
+### Docker Compose and ARM64
+
+If you’re working or want to host on an ARM64 system (such as Apple Silicon (M1/M2)) you’ll need to use the `arm` tag in your `docker-compose.yml` file:
+```yaml
+image: freshrss/freshrss:arm
+```
+
+If you then get this error message when running `docker compose up`:
+
+> The requested image's platform (linux/arm/v7) does not match the detected host platform (linux/arm64/v8) and no specific platform was requested
+
+… you will also need to specify the platform in the `service` part:
+
+```yaml
+services:
+  freshrss:
+    image: freshrss/freshrss:arm
+    platform: linux/arm/v7
+    container_name: freshrss
+ ```
+
 ## Run in production
 
 For production, it is a good idea to use a reverse proxy on your host server, providing HTTPS.