diff --git a/admin/inc/class.admin_customfields.inc.php b/admin/inc/class.admin_customfields.inc.php
index c8fc382c7b..4d77cd927c 100644
--- a/admin/inc/class.admin_customfields.inc.php
+++ b/admin/inc/class.admin_customfields.inc.php
@@ -377,6 +377,13 @@ class admin_customfields
 						{
 							$values['@'] = substr($content['cf_values'], $content['cf_values'][1] === '=' ? 2:1);
 						}
+						elseif (isset($GLOBALS['egw_info']['apps'][$content['cf_type']]))
+						{
+							if (!empty($content['cf_values']) && ($content['cf_values'][0] !== '{' || ($values=json_decode($content['cf_values'])) === null))
+							{
+								Api\Etemplate::set_validation_error('cf_values', lang('Invalid JSON object!'));
+							}
+						}
 						else
 						{
 							foreach(explode("\n",trim($content['cf_values'])) as $idx => $line)
@@ -459,7 +466,10 @@ class admin_customfields
 			{
 				$readonlys['cf_name'] = true;
 			}
-			$content['cf_values'] = json_decode($content['cf_values'], true);
+			if (!isset($GLOBALS['egw_info']['apps'][$content['cf_type']]))
+			{
+				$content['cf_values'] = json_decode($content['cf_values'], true);
+			}
 		}
 		else
 		{
diff --git a/api/js/etemplate/Et2Link/Et2LinkEntry.ts b/api/js/etemplate/Et2Link/Et2LinkEntry.ts
index 55a030fc5c..14b64651d1 100644
--- a/api/js/etemplate/Et2Link/Et2LinkEntry.ts
+++ b/api/js/etemplate/Et2Link/Et2LinkEntry.ts
@@ -73,7 +73,13 @@ export class Et2LinkEntry extends Et2InputWidget(FormControlMixin(SlotMixin(LitE
 			/**
 			 * Displayed in the search / select when no value is selected
 			 */
-			placeholder: {type: String}
+			placeholder: {type: String},
+
+			/**
+			 * Additional search parameters that are passed to the server
+			 * when we query searchUrl
+			 */
+			searchOptions: {type: Object}
 		}
 	}
 
@@ -219,6 +225,19 @@ export class Et2LinkEntry extends Et2InputWidget(FormControlMixin(SlotMixin(LitE
 		return this._appNode?.value || "";
 	}
 
+	set searchOptions(options)
+	{
+		this.updateComplete.then(() =>
+		{
+			this._searchNode.searchOptions = options;
+		});
+	}
+
+	get searchOptions()
+	{
+		return this._searchNode.searchOptions;
+	}
+
 	get _appNode() : Et2LinkAppSelect
 	{
 		return this.querySelector("[slot='app']");
diff --git a/api/js/etemplate/et2_extension_customfields.ts b/api/js/etemplate/et2_extension_customfields.ts
index a8a4360649..d4abbc01ad 100644
--- a/api/js/etemplate/et2_extension_customfields.ts
+++ b/api/js/etemplate/et2_extension_customfields.ts
@@ -284,7 +284,8 @@ export class et2_customfields_list extends et2_valueWidget implements et2_IDetac
 
 				const type = attrs.type ? attrs.type : field.type;
 				// Set any additional attributes set in options, but not for widgets that pass actual options
-				if(['select','radio','radiogroup','checkbox','button'].indexOf(field.type) == -1 && !jQuery.isEmptyObject(field.values))
+				if(['select','radio','radiogroup','checkbox','button'].indexOf(field.type) == -1 &&
+					setup_function !== '_setup_link_entry' && !jQuery.isEmptyObject(field.values))
 				{
 					const w = et2_registry[type];
 					const wc = window.customElements.get('et2-' + type);
@@ -769,6 +770,7 @@ export class et2_customfields_list extends et2_valueWidget implements et2_IDetac
 
 		attrs.type = "link-entry";
 		attrs[attrs.readonly ? "app" : "only_app"] = typeof field.only_app == "undefined" ? field.type : field.only_app;
+		attrs.searchOptions = {filter: field.values || {}};
 		return true;
 	}