fix layer loading for custom bundles

Author: clemiller

CHANGELOG.md

@@ -9,6 +9,12 @@
     The creation of the tag can be disabled with the --no-git-tag-version if desired.
 -->
 
+# 5.3.1 - 6 April 2026
+
+## Fixes
+- Fixed an issue where layers created from a custom STIX bundle would fail to load when re-opened via "Open Existing Layer". See [#775](https://github.com/mitre-attack/attack-navigator/issues/775).
+
+
 # 5.3.0 - 15 January 2026
 
 ## Improvements

nav-app/package-lock.json

@@ -5,7 +5,7 @@
     "type": "git",
     "url": "https://github.com/mitre-attack/attack-navigator.git"
   },
-  "version": "5.3.0",
+  "version": "5.3.1",
   "license": "Apache-2.0",
   "scripts": {
     "ng": "ng",

nav-app/package.json

@@ -788,12 +788,12 @@ export class TabsComponent implements AfterViewInit {
                         let layerVersionStr = viewModel.deserializeDomainVersionID(layerObj);
                         await self.versionMismatchWarning(layerVersionStr);
                         self.versionMismatchWarning(layerVersionStr);
-                        if (!self.dataService.getDomain(viewModel.domainVersionID)) {
-                            throw new Error(`Error: '${viewModel.domain}' (v${viewModel.version}) is an invalid domain.`);
-                        }
-
+                        
                         let isCustom = 'customDataURL' in layerObj;
                         if (!isCustom) {
+                            if (!self.dataService.getDomain(viewModel.domainVersionID)) {
+                                throw new Error(`Error: '${viewModel.domain}' (v${viewModel.version}) is an invalid domain.`);
+                            }
                             await self.upgradeLayer(viewModel, layerObj, true);
                             console.debug(`loaded layer "${viewModel.name}"`);
                         } else {