When using the Server > Retrieve Keys... feature of GPA to fetch a remote key from a key server or a Web Key Directory, GPA reports that No keys were found. However, when asking to see the Details, one can see that GPG actually successfully imported the desired key:
[GPA 0.11.0-beta5, GPGME 1.12.1-beta113, GnuPG 2.3.0-beta562] gpg: key F2AD85AC1E42B367: public key "[User ID not found]" imported gpg: Total number processed: 1 gpg: imported: 1
And when refreshing the key listing after closing the dialog, the imported key is indeed present in the keyring.
This seems independent of the actual key requested. I tested with several keys that I know are available either in a WKD or in the keyserver network, for the same result.
I initially observed this behavior with GPA 0.10.0, GnuPG 2.2.12, GpgME 1.12.0. I reproduced it with freshly built binaries from the master branch of all projects.