Virtual Agent client loading blank screen on the Service Portal - Known Error

Virtual Agent client loading blank screen on the Service Portal Description Virtual Agent client was loading blank screen on the Service Portal, as shown in the below screenshot,

While reproducing the issue, we could see below stack on the node logs or session debug logs,

01:11:00.159 Streaming error: com.glide.rest.util.RESTRuntimeException: Streaming error: com.glide.rest.serializer.impl.ResponseSerializerImpl.serializeStream(ResponseSerializerImpl.java:137) com.glide.rest.handler.impl.ServiceResultHandlerImpl.serialize(ServiceResultHandlerImpl.java:128) com.glide.rest.handler.impl.ServiceResultHandlerImpl.processServiceResultBody(ServiceResultHandlerImpl.java:96) com.glide.rest.handler.impl.ServiceResultHandlerImpl.processServiceResult(ServiceResultHandlerImpl.java:40) com.glide.rest.processors.RESTAPIProcessor.process(RESTAPIProcessor.java:290) com.glide.processors.AProcessor.runProcessor(AProcessor.java:553) com.glide.processors.AProcessor.processTransaction(AProcessor.java:241) com.glide.processors.ProcessorRegistry.process0(ProcessorRegistry.java:177) com.glide.processors.ProcessorRegistry.process(ProcessorRegistry.java:166) com.glide.ui.GlideServletTransaction.process(GlideServletTransaction.java:31) com.glide.sys.Transaction.run(Transaction.java:2218) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) java.lang.Thread.run(Thread.java:748)

01:11:00.160 #37470 [REST API] RESTAPIProcessor : Handling exception Streaming error

01:11:00.160 #37470 [REST API] RESTAPIProcessor : Unknown exception RESTRuntimeException:Streaming errorDetail: No serializer found for class com.glide.db.datamodel.ShortTableName and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: com.glide.cs.qlue.dto.SessionResponseV2Dto["brandingSettings"]->com.glide.cs.qlue.module.adminconsole.BrandingSettings["virtualAgentUser"]->com.glide.sys.User["companyRecord"]->com.glide.script.GlideRecord["elements"]->java.util.ArrayList[0]->com.glide.script.glide_elements.GlideElementUserImage["ed"]->com.glide.db.ElementDescriptor["shortTableName"])

01:11:00.160 #37470 [REST API] ResponseSerializer : Streaming exception (won't rethrow): write beyond end of stream

Steps to Reproduce

1. Log onto an Instance

2. Navigate to Service Portal

3. Click on "Virtual Agent" icon

Result:

Observe that Virtual Agent screen loads blank

Workaround This issue has been fixed in Orlando Patch 3 and Paris releases. Please upgrade to one of the fixed in version to get the fix and resolve the issue.

If upgrade not possible, apply the following to resolve the issue,

Make sure "com.glide.cs.va.sys_user" system property is set with OOB provided virtual.agent user (sys_id=3c69f4ecdb941c109acb5947f49619ca). Then make sure that virtual.agent user record is not set with any company