Fix bugs and improve UX based on a test

[DarthVanger]

Johnny has tested the app and found a number of bugs and possible UX improvements.

There is a 17 min video: https://photos.app.goo.gl/xzqvS69zyD6gyCKi8 And another one 1 min video: https://photos.app.goo.gl/XKDdE5nCRq6wRqNHA

And also there is video of Johnny playing Violin: https://photos.app.goo.gl/mxF7wdeD8DRxvTzi7

To do

• [ ] Watch the video, cutting it into pieces: a small video for each particular bug
• [ ] Create a github issue for each small piece
• [ ] Describe the bug with text: steps to reproduce, actual behvaiour, expected behaviour
• [ ] Add screenshots
• [ ] Upload the video somewhere and share the link in the github issue
• [ ] Label each github issue as bug or UX bug / improvement