diff --git a/test/controller/Controller.js b/test/controller/Controller.js
index 76eec466..8a8b5edf 100644
--- a/test/controller/Controller.js
+++ b/test/controller/Controller.js
@@ -14,6 +14,7 @@ import {
 	addPluginConfigFields, renamePermissionPrefix,
 } from "@clusterio/lib";
 
+import * as lib from "@clusterio/lib";
 import "../setup_logging.js";
 
 class MockEvent {}
@@ -88,6 +89,45 @@ describe("controller/src/Controller", function() {
 				assert(loaded.modPacks.size > 0, "default mod packs were not added");
 				await fs.access(modsDirectory);
 			});
+			describe("with a plugin version change", function() {
+				before(function() {
+					addPluginConfigFields([{ name: "from_config_plugin", version: "1.2.0", instanceEntrypoint: "x" }]);
+				});
+				afterEach(function() {
+					lib.Config.pluginVersions.clear();
+				});
+				after(function() {
+					for (const Config of [lib.ControllerConfig, lib.HostConfig, lib.InstanceConfig]) {
+						for (const name of Object.keys(Config.fieldDefinitions)) {
+							if (name.startsWith("from_config_plugin.")) {
+								delete Config.fieldDefinitions[name];
+							}
+						}
+					}
+				});
+				it("should save instances whose config changed while loading", async function() {
+					const databaseDirectory = path.join(dir, "database");
+					const instancesPath = path.join(databaseDirectory, "instances.json");
+					await fs.mkdir(databaseDirectory);
+					const instanceConfig = new InstanceConfig("controller", {
+						"instance.id": 7, "from_config_plugin.version": "1.0.0",
+					});
+					await fs.writeFile(instancesPath, JSON.stringify([
+						{ config: instanceConfig.toJSON(), status: "unassigned" },
+					]));
+					lib.Config.pluginVersions.set("from_config_plugin", "1.2.0");
+					const config = new ControllerConfig("controller", {
+						"controller.version": controllerVersion,
+						"controller.database_directory": databaseDirectory,
+						"controller.mods_directory": path.join(dir, "mods"),
+					});
+
+					const loaded = await Controller.fromConfig({}, [], config);
+					await loaded.instances.records.save();
+					const [saved] = JSON.parse(await fs.readFile(instancesPath, "utf8"));
+					assert.equal(saved.config["from_config_plugin.version"], "1.2.0");
+				});
+			});
 		});
 		describe(".loadJsonObject()", function() {
 			let dir;