diff --git a/scripts/exporter/retrobat_exporter.py b/scripts/exporter/retrobat_exporter.py
index 22ce255c..c14d064f 100644
--- a/scripts/exporter/retrobat_exporter.py
+++ b/scripts/exporter/retrobat_exporter.py
@@ -7,6 +7,7 @@ state md5 then file, in that order.
 from __future__ import annotations
 
 import json
+import re
 from collections import OrderedDict
 
 from .base_exporter import BaseExporter
@@ -18,6 +19,33 @@ SOURCE_URL = (
 )
 
 
+_TOP_KEY = re.compile(r'^  "((?:[^"\\]|\\.)*)":', re.MULTILINE)
+
+
+def keep_blank_lines(original: str, produced: str) -> str:
+    """The blank line RetroBat writes before each system, written again.
+
+    json.dumps has no blank lines, and the original separates every system
+    after the first with one: dropped, they were 100 hunks of a diff meant
+    to show corrections. A system the original separates is separated, and
+    where it separates them all, an added one is too.
+    """
+    keys = _TOP_KEY.findall(original)
+    separated = set(re.findall(r'\n\n  "((?:[^"\\]|\\.)*)":', original))
+    every = bool(keys) and separated == set(keys[1:])
+    first = True
+
+    def separate(match: re.Match[str]) -> str:
+        nonlocal first
+        key, was_first = match.group(1), first
+        first = False
+        if not was_first and (key in separated or (every and key not in keys)):
+            return "\n" + match.group(0)
+        return match.group(0)
+
+    return _TOP_KEY.sub(separate, produced)
+
+
 class Exporter(BaseExporter):
     """Write RetroBat's batocera-systems.json, corrected."""
 
@@ -105,7 +133,8 @@ class Exporter(BaseExporter):
             output[key] = system_entry
 
         text = json.dumps(output, indent=2, ensure_ascii=False) + "\n"
-        return {self.native_filename(): text}
+        original = (originals or {}).get(self.native_filename(), "")
+        return {self.native_filename(): keep_blank_lines(original, text) if original else text}
 
     def validate(
         self,
diff --git a/tests/test_exporters.py b/tests/test_exporters.py
index 67351c8f..840898f1 100644
--- a/tests/test_exporters.py
+++ b/tests/test_exporters.py
@@ -1420,6 +1420,31 @@ class BizhawkExport(unittest.TestCase):
         self.assertFalse(exporter.states(entry, "sha1"))
 
 
+class RetrobatListComesBackAsWritten(unittest.TestCase):
+    """RetroBat separates each system with a blank line. json.dumps dropped
+    all 100 of them, 100 hunks of noise in a diff meant to show
+    corrections."""
+
+    def test_an_empty_truth_hands_back_the_list(self):
+        original_path = UPSTREAM_CACHE / "retrobat" / "batocera-systems.json"
+        if not original_path.exists():
+            self.skipTest("upstream cache not populated")
+        original = original_path.read_text(encoding="utf-8")
+        exporter = discover_exporters()["retrobat"]()
+        config = native_layer(load_platform_config("retrobat", str(REPO_ROOT / "platforms")))
+        systems, report = build_native_model({"systems": {}}, config)
+        produced = exporter.render(systems, report, {"batocera-systems.json": original}, config)
+        self.assertEqual(produced["batocera-systems.json"], original)
+
+    def test_an_added_system_takes_the_same_separator(self):
+        from exporter.retrobat_exporter import keep_blank_lines  # noqa: PLC0415
+
+        original = '{\n  "a": {},\n\n  "b": {}\n}\n'
+        produced = '{\n  "a": {},\n  "b": {},\n  "c": {}\n}\n'
+        self.assertEqual(keep_blank_lines(original, produced),
+                         '{\n  "a": {},\n\n  "b": {},\n\n  "c": {}\n}\n')
+
+
 class MisterDatabaseComesBackAsWritten(unittest.TestCase):
     """The BiosDB is one line of JSON. Written with indent=2 it came out as
     1499 changed lines for a database whose content had not changed."""