seguimos los pasos de https://docs.gitea.io/en-us/customizing-gitea/#customizing-gitea para poner templates personalizados

Dockerfile

@@ -34,8 +34,11 @@ RUN ln -s /app/gitea/gitea /usr/local/bin/gitea && \
     ln -s /data /app/gitea/data
 
 # Copy mods on templates
+# https://docs.gitea.io/en-us/customizing-gitea/#customizing-gitea-pages-and-resources
+# 
 # we do hide 'users' from public listing
-COPY users.tmpl /app/gitea/templates/explore/users.tmpl
+RUN mkdir -p /data/templates/explore/
+COPY users.tmpl /data/templates/explore/users.tmpl
 
 VOLUME ["/data"]
 ENV GITEA_CUSTOM /data