FB messenger is slow and creepy. It drains the fuck out of the battery with its incessant spying. Is there a decent open source wrapper / alternative that uses the fb network?
Is that the same as what is called “Chat” on my Facebook? Like “video chat” and “voice call”?
Spying?
Heh, I use Messenger without any problems. I prefer WhatsApp, though.
Facebook Messenger drains the hell out of my battery also. Pisses me off. Luckily I don’t use it all that much.
Signal. It’s secure, and it’s not owned by Facebook.
If you must use Facebook to contact people, delete the Messenger app and go to Facebook via your phone’s browser. Once on Facebook, go to your browser’s option list (mine’s in the upper right corner of my phone screen) and select Request Desktop. Then you can use the Chat/Messaging function sans the Messenger app and all its attendant issues.
Also owned by Facebook. Which is a company I don’t trust at ALL, which is why I have precisely zero FB apps on my phone. I don’t even use the phone browser to go to FB, that’s for my laptop, which can’t blab my location or take pics of me when I’m not looking. 
They may not show the location in your posts from your laptop, but Facebook sees it and sells it.
I use an app called Metal which opens FB and/or twitter in its own browser. My battery life is much better without FB and Messenger!