diff --git a/oci/catalog/apps/filebrowser-quantum.json b/oci/catalog/apps/filebrowser-quantum.json
index e8c88aab..e22d2981 100644
--- a/oci/catalog/apps/filebrowser-quantum.json
+++ b/oci/catalog/apps/filebrowser-quantum.json
@@ -304,7 +304,7 @@
           "mode": "0644",
           "owner": "mapped-application-user",
           "only_if_missing": true,
-          "content": "server:\n  port: 80\n  cacheDir: /home/filebrowser/data/tmp\n  sources:\n    - path: /folder\n      config:\n        defaultEnabled: true\nauth:\n  adminUsername: admin\n"
+          "content": "http:\n  port: 80\nserver:\n  cacheDir: /home/filebrowser/data/tmp\n  sources:\n    - path: /folder\n      config:\n        defaultEnabled: true\nauth:\n  adminUsername: admin\n"
         }
       ],
       "startup_healthcheck": {
diff --git a/oci/catalog/curated/filebrowser-quantum.json b/oci/catalog/curated/filebrowser-quantum.json
index 6fc1c187..f75a34ff 100644
--- a/oci/catalog/curated/filebrowser-quantum.json
+++ b/oci/catalog/curated/filebrowser-quantum.json
@@ -304,7 +304,7 @@
           "mode": "0644",
           "owner": "mapped-application-user",
           "only_if_missing": true,
-          "content": "server:\n  port: 80\n  cacheDir: /home/filebrowser/data/tmp\n  sources:\n    - path: /folder\n      config:\n        defaultEnabled: true\nauth:\n  adminUsername: admin\n"
+          "content": "http:\n  port: 80\nserver:\n  cacheDir: /home/filebrowser/data/tmp\n  sources:\n    - path: /folder\n      config:\n        defaultEnabled: true\nauth:\n  adminUsername: admin\n"
         }
       ],
       "startup_healthcheck": {
diff --git a/oci/remote/install_oci.sh b/oci/remote/install_oci.sh
index 3b2e11c6..53c23b5a 100755
--- a/oci/remote/install_oci.sh
+++ b/oci/remote/install_oci.sh
@@ -330,6 +330,8 @@ INSTALL_COMPLETE=0
 PRESERVE_FAILED_CT=0
 VOLUME_SEED_STAGE_ROOT=""
 VOLUME_SEED_TARGETS=()
+# The volumes that have just been filled with what the image has at their path.
+VOLUME_SEEDED_NOW=()
 VOLUME_SEED_STAGES=()
 VOLUME_SEED_MOUNT_TYPES=()
 CANONICAL_INPUT_DIR=""
@@ -553,12 +555,23 @@ apply_volume_seeds() {
       || { oci_log "Could not seed the persistent volume from the image: $target"; failed=1; break; }
     rm -rf -- "$stage" \
       || { oci_log "Could not remove the temporary image data: $target"; failed=1; break; }
+    VOLUME_SEEDED_NOW+=("$target")
     oci_log "Image data copied into the new persistent volume: $target"
   done
   cleanup_volume_seed_staging || { oci_log "Could not remove the temporary image-volume staging directory"; failed=1; }
   (( failed == 0 ))
 }
 
+# Whether a path sits in a volume that has just been filled from the image.
+# What is there is the copy the image ships, not a file the user kept.
+filled_from_the_image() {
+  local path=$1 target
+  for target in "${VOLUME_SEEDED_NOW[@]}"; do
+    [[ $path == "$target"/* ]] && return 0
+  done
+  return 1
+}
+
 prepare_file_mount_target() {
   local requested_target=$1
   local rootfs="/var/lib/lxc/${VMID}/rootfs"
@@ -1162,8 +1175,13 @@ apply_installer_profile() {
       rm -f "$merged_file"
     fi
     if [[ $(jq -r '.only_if_missing // false' <<<"$item") == true && -e $destination ]]; then
-      oci_log "Keeping the existing persistent file: $path"
-      continue
+      if ! filled_from_the_image "$path"; then
+        oci_log "Keeping the existing persistent file: $path"
+        continue
+      fi
+      # The file of the recipe is the starting configuration: it takes the
+      # place of the one the image ships, never of one the user already had.
+      oci_log "The generated file replaces the one of the image: $path"
     fi
     install -D -m "$mode" /dev/null "$destination" || { failed=1; break; }
     jq -er '.content' <<<"$item" >"$destination" || { failed=1; break; }
diff --git a/oci/tests/test_generated_file_over_image_copy.py b/oci/tests/test_generated_file_over_image_copy.py
new file mode 100644
index 00000000..b63da17f
--- /dev/null
+++ b/oci/tests/test_generated_file_over_image_copy.py
@@ -0,0 +1,73 @@
+"""A new volume starts with what the image has at its path, and a recipe may
+write its own starting file in it. The file of the recipe wins over the copy of
+the image; a file the user already had, in a reused volume or a host
+directory, is kept."""
+
+from pathlib import Path
+import re
+import shutil
+import subprocess
+import sys
+import unittest
+
+ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(ROOT / "src"))
+
+from proxmenux_oci.catalog import Catalog
+
+INSTALLER = (ROOT / "remote/install_oci.sh").read_text()
+
+
+def function(name):
+    found = re.search(rf"^{name}\(\) \{{\n.*?^\}}\n", INSTALLER, re.S | re.M)
+    assert found, name
+    return found.group(0)
+
+
+class GeneratedFileTests(unittest.TestCase):
+    def filled(self, path, *volumes):
+        script = f'VOLUME_SEEDED_NOW=({" ".join(volumes)})\n{function("filled_from_the_image")}\nfilled_from_the_image "$1" && echo yes || echo no'
+        done = subprocess.run(["bash", "-c", script, "bash", path], capture_output=True, text=True, check=False)
+        self.assertEqual(done.stderr, "")
+        return done.stdout.strip()
+
+    @unittest.skipUnless(shutil.which("bash"), "bash is needed")
+    def test_a_file_in_a_volume_just_filled_is_the_copy_of_the_image(self):
+        self.assertEqual(self.filled("/home/filebrowser/data/config.yaml", "/home/filebrowser/data"), "yes")
+        self.assertEqual(self.filled("/config/app/settings.yml", "/data", "/config"), "yes")
+
+    @unittest.skipUnless(shutil.which("bash"), "bash is needed")
+    def test_a_file_anywhere_else_is_not(self):
+        self.assertEqual(self.filled("/home/filebrowser/data/config.yaml"), "no")
+        self.assertEqual(self.filled("/home/filebrowser/database/config.yaml", "/home/filebrowser/data"), "no")
+        self.assertEqual(self.filled("/home/filebrowser/data", "/home/filebrowser/data"), "no")
+
+    def test_only_a_volume_that_was_filled_is_recorded(self):
+        body = function("apply_volume_seeds")
+        copied = body.index('cp -a -- "${stage}/." "${destination}/"')
+        self.assertLess(copied, body.index('VOLUME_SEEDED_NOW+=("$target")'))
+        # A host directory that already holds data is kept and not recorded.
+        self.assertLess(body.index("Keeping existing host data without seeding it"), copied)
+
+    def test_the_recipe_file_is_written_over_the_copy_of_the_image_only(self):
+        step = INSTALLER[INSTALLER.index("generated_count=$(jq"):INSTALLER.index("generated_created=$((generated_created + 1))")]
+        self.assertLess(step.index("apply_volume_seeds"), step.index("only_if_missing"))
+        kept = step.index('if ! filled_from_the_image "$path"; then')
+        self.assertLess(kept, step.index("Keeping the existing persistent file"))
+        self.assertLess(step.index("Keeping the existing persistent file"), step.index("The generated file replaces the one of the image"))
+
+    def test_filebrowser_quantum_serves_the_folder_it_mounts(self):
+        template = Catalog(ROOT).compose("filebrowser-quantum")
+        volumes = [item["container_path"] for item in template["container_contract"]["volumes"]]
+        generated = template["proxmox"]["installer_profile"]["generated_files"][0]
+        served = re.search(r"sources:\s*\n\s*- path: (\S+)", generated["content"]).group(1)
+        self.assertIn(served, volumes)
+        self.assertTrue(any(generated["container_path"].startswith(volume + "/") for volume in volumes))
+        self.assertTrue(generated["only_if_missing"])
+        # FileBrowser Quantum 2 reads the port under http, not under server.
+        self.assertRegex(generated["content"], r"(?m)^http:\n  port: 80$")
+        self.assertNotRegex(generated["content"], r"(?m)^server:\n  port:")
+
+
+if __name__ == "__main__":
+    unittest.main()