Fix the PHP Docker image

app/Http/Controllers/Frontend/HomeController.php

@@ -29,6 +29,11 @@ class HomeController extends Controller
             return view('system/errors/not_installed');
         }
 
+        // No users
+        if (!$users) {
+            return view('system/errors/not_installed');
+        }
+
         return view('home', [
             'users' => $users,
         ]);

docker/php/Dockerfile

@@ -1,13 +1,12 @@
 FROM php:7.3-fpm
 
-RUN docker-php-ext-install \
-    mysqli \
-    pdo \
-    openssl \
-    mbstring \
-    tokenizer \
-    curl \
-    json \
-    gmp
+RUN apt-get update
+RUN apt-get install -y libgmp-dev
 
 RUN ln -sf /dev/stderr /var/log/fpm-error.log
+
+RUN docker-php-ext-install \
+  mysqli \
+  pdo \
+  pdo_mysql \
+  gmp