When using e2e encryption (secret chats), the answer is obviously no (I hope), but I am talking about NOT e2e-encrypted messages, the ones stored in the cloud.
I am of course aware that the messages are travelling on SSL encrypted connections, but are the body of the messages encrypted in any way when they reach Google/Firebase Cloud Message, APN and other 3rd party push notifications services?
In other words, if I send a message to Bob over a NON-secret chat, can Google, Apple, etc. read the body of the message I sent to him when it passes through their push notifications servers?