I know #Signal is very popular, but at least for me, using NVDA, the desktop client is far less screen reader friendly than the mobile clients. The mobile clients work far better for me, but I honestly don't use my phone for much these days outside of being a media player that can make phone calls, so, as of right now, I'd recommend Delta Chat instead https://delta.chat/en/ #DeltaChat
Delta Chat: Delta Chat, decentralized secure messenger

Delta Chat is a decentralized and secure messenger app 💬 Reliable instant messaging with multi-profile and multi-device support ⚡️ Sign up to secure and interoperable chatmail relays 🥳 Interactive ...

@clv1 @WeirdWriter I tried Delta a few years ago and found hte desktop client very unimpressive and the mobile clients had real access issues around voice messages. Have these things been bettered?
@nick @WeirdWriter I don't know about mobile; on desktop, I wouldn't call it most productive, but accessible and usable yes.
@clv1 @nick @WeirdWriter Snikket Chat is also a strong contender, given its use of a well-established XMPP protocol. Once a more modern and native XMPP app is developed that is able to take advantage of the improvements to the spec made on the part of Snikket, that is. Miranda IM's support of groupchats is underdeveloped, and Pigeon just isn't very accessible on the Windows side. https://snikket.org/
Snikket Chat

Snikket is a simple, secure and private messaging app

Snikket Chat
@jackf723 @nick @WeirdWriter Thanks for this; I didn't know it.
@clv1 @nick @WeirdWriter Native app development is/should be made significantly easier by their Borogove SDK. Their post about it:
https://snikket.org/blog/borogove-the-new-snikket-sdk/
And the main page for the SDK proper:
https://borogove.dev/
Introducing Borogove, the new Snikket SDK

Our in-development SDK finally has its own name.

Snikket Chat