Not Valid Error When Creating a Rule to Limit Events

[bhaynes777]

I am attempting to use Metrics Aggregator to create an Events to Metrics rule that is limited to certain events. When selecting an attribute and creating a condition, I always get a "Not Valid" error message on the screen under the condition:

Additionally, in the Chrome DevTools, I see this error after the tool is validating the NRQL clause:

TypeError: Cannot read properties of null (reading 'results')
at 932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet9ba30d97.js:1:38850
at c (vendors932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet22e23f9c.js:1:137851)
at Generator._invoke (vendors932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet22e23f9c.js:1:137604)
at Generator.next (vendors932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet22e23f9c.js:1:138214)
at r (vendors932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet22e23f9c.js:1:201661)
at a (vendors932f5c04-5ab6-47d9-90ab-0e716237a4a3--e2m-gui-nerdlet~22e23f9c.js:1:201864)

The event source type is Transaction, with summary(1):

I think this may be the same as this closed issue: #36