Open Notes and click into text section of notes. This will open up your keyboard.
Once you are done typing click “save” to save to your notes AND click “Done” to close your keyboard
This will collapse the keyboard view and you should now see the “x” icon to exit your note back to the page you were just on.
We are investigating a bug on some Android devices, not allowing Notes to Save on Firefox web browser. We do have this on our development list to explore. We may or may not be able to get this feature working in the next few months, due to the complexities of cross-platform devices and web browsers.
Please try using a different web browser on Android devices.
We will have more updates on cross-platform mobile improvements by February 2021.