Bridge 2021, change keyword separator to a comma ppleeaaseeee!!

After collating code fragments from other contributors on these forums I have hacked together a script for Bridge (Ver 13) that will copy the keywords of the selected asset to the Windows clipboard, delimited by commas, suitable for pasting into websites that require commas.

I have tested only on Windows 10, Bridge 13, with JPG and RAF image files.

/*
Filename: CopyKeywords.jsx

Script cobbled together by Andy Millard based on code fragments from 
contributors on the Adobe Support Community, including Stephen Marsh

When triggered by a new context menu item, this script accesses the 
metadata of the first selected asset and copies the keywords 
to the system clipboard, delimited by a commas.

Install by copying to the Startup Scripts folder of Bridge

Last modifed 9/28/2023

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#target bridge
if(BridgeTalk.appName == 'bridge')
{
    try{
		// Load the XMPScript library
		if ( ExternalObject.AdobeXMPScript == undefined ) 
		{
			ExternalObject.AdobeXMPScript = new ExternalObject( "lib:AdobeXMPScript" );		
		}
		// Add new action to the Context menu of selected asset
        var xmpCommand = MenuElement.create('command', 'Copy Keywords to Clipboard', 'after Thumbnail/Open', this.menuID);

		// Set the function to be called for the new action
        xmpCommand.onSelect = function()
		{
			keysToClipboard();
        }

		function keysToClipboard()
		{
			// Tested on Windows with Bridge version 13
			// I suspect it may not work with earlier versions of Bridge
			if(BridgeTalk.appVersion > 12)
			{
				var thumb = app.document.selections[0]; // Get first selected thumbnail
				app.synchronousMode = true; // Ensure recent metadata changes are included
				var xmp = new XMPMeta(thumb.synchronousMetadata.serialize());
				
				// Count number of keywords
				var items = xmp.countArrayItems(XMPConst.NS_DC, 'subject');  
				// Collect the keywords
				var keys = [];
				for(var i = 1;i <= items;i++)
				{
					// To access the keywords from the metadata, use the NS_DC namespace 
					// and "subject".
					keys.push(xmp.getArrayItem(XMPConst.NS_DC, 'subject', i));  
				}  
				// Delimit the keywords with comma	
				keys = (keys.join(', '));
				// Copy the keywords string to the system clipboard
				app.document.copyTextToClipboard(keys.toString());
			}
			else
			{
				alert("Script not tested with this version of Bridge");
			}
        }
    }
	catch(e){
		alert(e + ' ' + e.line);
    }
}