The dev seems new to this. Here are the patch notes:
Bugfixes:
- Trainers cannot see you if you are in a menu or saving.
- The “options” option has been removed from the start menu.
- Freeze when interacting with Poké Balls after getting the first Pokémon in the professor's lab.
- Volatile status such as drain and confusion now disappear.
- Poison powder bug fixed.
- Hide battle background is save file.
- When a Pokémon receives an attack to which it is immune, it now reacts correctly.
- The number of Pokémon you have in the Pokédex now appears in the trainer tab and on the save screen.