Describe how to use the latest features in Docker

README.md

@@ -98,8 +98,13 @@ docker container start doccano
 
 Go to <http://127.0.0.1:8000/>.
 
-To stop the container, run `docker container stop doccano -t 5`.
-All data created in the container will persist across restarts.
+To stop the container, run `docker container stop doccano -t 5`. All data created in the container will persist across restarts.
+
+If you want to use the latest features, please specify `nightly` tag:
+
+```bash
+docker pull doccano/doccano:nightly
+```
 
 ### Docker Compose
 

docs/install_and_upgrade_doccano.md

@@ -160,6 +160,12 @@ docker container start doccano
 To stop the container, run `docker container stop doccano -t 5`.
 All data created in the container persist across restarts.
 
+If you want to use the latest features, please specify `nightly` tag:
+
+```bash
+docker pull doccano/doccano:nightly
+```
+
 ### Build a local image with Docker
 
 If you want to build a local image, run: