Keyboard automatically closing after each character input
Using on HTC 10, Android 8.0.0, GeoGebra Graphing Calculator application version 5.0.540.0 (as it says in the Play store).
I can type only one character or function on GeoGebra keyboard (that is, click on one button/entry on keyboard), and then the keyboard automatically closes. I have to type each character separately, opening the keyboard for each one. Reinstalling application didn't help, nor did clearing data, wiping cache partition, etc.
However, adding objects works just fine. The problem is only in the keyboard, as it seems.
I hope the amount of details help you solve this.