API filter for string custom fields doesn't work properly

[llamafilm]

Deployment Type

Self-hosted

NetBox Version

v4.3.2

Python Version

3.12

Steps to Reproduce

1. Create a string type custom field called FWversion.
2. Set this value to 1 on one device, and 10 for another device.
3. Filter using dcim/devices/?cf_FWversion=1

Expected Behavior

It should return only the device with exactly matching value, according to the documentation:

To filter results by a custom field value, prepend cf_ to the custom field name. For example, the following query will return only sites where a custom field named foo is equal to 123:
GET /api/dcim/sites/?cf_foo=123

Observed Behavior

It returns both devices. I believe it returns all devices where that field contains the value instead of an exact match.