Whispering Players from different Server bugged?

Hi Helistab,

We just deployed a new hotfix that should resolve this issue. In order to download the new client hotfix, you may need to close out of your WoW Client and allow your Battle.net app to download the new version (you should have 1.14.4.50156).

After logging back in, this should work as it did prior to patch 1.14.4. Thank you for the report!