I recently just upped my StandardNotes subscription (the Black Friday ad is still active), and I'm now locked in for ~5.5 years. It's a very plain-text webapp/mobile app that aims to be simple and long-lasting, yet feature-full by means of optional extensions. It's not perfect, but I've been using it for a few months now without any data loss/major bugs encountered, and was excited to use it to ditch Google Keep/Google Authenticator.
It's amazing what you can do with simple text, especially with a Markdown-supporting editor.
It's amazing what you can do with simple text, especially with a Markdown-supporting editor.