How to reproduce:
1. Open the project "case_1249443-Addressables_Enter"
2. Open the Scene "SampleScene"
3. Select the GameObject "Test" in the Inspector
4. Select "Asset Reference Sprite 2" in the "Test (Script)" in the Inspector
5. Press the 'Enter' key

Expected results: the dropdown of Addressable Assets of the field "Asset Reference Sprite 2" is opened
Actual results: the dropdown of Addressable Assets of the field "Asset Reference Sprite 1" is opened

Reproducible with: 1.8.3 (2018.4.23f1, 2019.3.14f1, 2020.1.0b9, 2020.2.0a12

Could not test with: 1.7.5 because the dropdown of Addressable Assets does not open when pressing 'Enter' key

Notes:
1. It is also reproducible when Sprite field instead of AssetReference is selected in the Inspector (see the attached video)