API call - Postman - select specific systemProperties - ?fields=

Based on this discussion I'm looking at this example in the API documentation:

https://www.logicmonitor.com/support/rest-api-developers-guide/v1/devices/get-devices#Example-Request-5--GET-all-devices-that-have-a-spe

And wondering about this example filter:

filter=customProperties.name:snmp.version,customProperties.value:v2c

It seems like what it should be doing is filtering on devices that have a customProperty named snmp.version with a value of "v2c". But what it may actually be doing is filtering on devices that have a customProperty with name snmp.version and/or (question?) a customProperty with a value of "v2c". Since all devices probably have the first condition it is probably moot, and also since no other property probably has a value of v2c it may actually work. But that's a bit of a stretch for any name:value pairs on real devices. Am I misunderstanding this?

I'm wanting to make a filter on system.collector equals true, but if the above is true, then all devices would match having a property with that name and matching a value of false is also equally useless. Any ideas how to return a list of devices via API that are collectors?