In the bottom right hand corner "Map data ©2018 Google" is repeated twice.
This appears to be due to the Maps API relying on global print CSS media rules that aren't cascaded into the shadow DOM in the component.
If the Shady DOM polyfill applies the bug is resolved.
More detail: https://stackoverflow.com/questions/50952506/how-do-a-remove-one-of-the-two-copyright-notices-on-google-maps/50987794#50987794