Use Etherpad 1.8.7, not :latest

roles/matrix-etherpad/defaults/main.yml

@@ -2,7 +2,7 @@ matrix_etherpad_enabled: false
 
 matrix_etherpad_base_path: "{{ matrix_base_data_path }}/etherpad"
 
-matrix_etherpad_docker_image: "docker.io/etherpad/etherpad:latest"
+matrix_etherpad_docker_image: "docker.io/etherpad/etherpad:1.8.7"
 matrix_etherpad_docker_image_force_pull: "{{ matrix_etherpad_docker_image.endswith(':latest') }}"
 
 # List of systemd services that matrix-etherpad.service depends on.
@@ -53,9 +53,9 @@ matrix_etherpad_database_connection_string: 'postgres://{{ matrix_etherpad_datab
 matrix_etherpad_title: 'Etherpad'
 matrix_etherpad_default_pad_text: |
   Welcome to Etherpad!
-  
+
   This pad text is synchronized as you type, so that everyone viewing this page sees the same text. This allows you to collaborate seamlessly on documents!
-  
+
   Get involved with Etherpad at https://etherpad.org
 
 # Default Etherpad configuration template which covers the generic use case.