??
Usually it’s the other way around. You’d want an app that’s being maintained.
Anyway, i use veracrypt as my go to app for encryption. https://www.veracrypt.fr/code/VeraCrypt/
I am not sure if it is available in Gnome at all but I use KDE Vaults on Plasma. It is super easy to set up, and use. The nice thing is, you can open and shut the vaults as needed. I think it is a much better method than file system encryption but that is just an opinion.
Thanks @CubicleNate and @Eltuxo I ran across a page that discussed LibreOffice file password protection and encryption. It’s perfect for my purposes. Thanks for your suggestions.
@astronautsupplier From what I can see 7zip for Linux only available in CLI mode. I don’t like CLI apps and avoid them when a GUI alternative is available.
Gnome Disks allows one to optionally LUKS-encrypt an EXT4 partition, at the time you create said partition. That’s my go-to for full-partition encryption.