@MockBean for a @FeignClient not working as it did in 2.2.5

[N4zroth]

I upgraded from 2.2.5 to 2.3.0. We have a @SpringBootTest that uses @MockBean on a @FeignClient. With 2.2.5, we were able to Mockito.when(...) to make the FeignClient return what we wanted in that specific test. After upgrading to 2.3.0, the @MockBean doesn't seem to work correctly: In debug mode I can see that in the test, we indeed have a Mockito mock for the client, in the tested code however it's not a mock but Spring's proxy thus crashing the test. The behaviour can be seen here https://github.com/N4zroth/spring-boot-feign-mockbean , the test fails with 2.3.0 but succeeds with 2.2.5.
I'm quite sure that the previous behavior was correct and the new one is wrong. Correct me if I'm wrong, though.

[snicoll]

Thanks for the report and the sample. This is a duplicate of #21379

[N4zroth]

Ah sorry somehow that didn't come up on Google. Thanks!