Oh, I see. Yeah, I had to click close to the light blue/turquoise glowing line around the toilet or just a lotta times to get there. Would be cool, if it would pop-up by clicking on the back-panel of the toilet, true.
Finally was able to progress. I clicked on the side of the toilet and the calibration screen popped up. And yeah, the game doesn't give the play any indication of where they should be click sometimes. Even just a little light appearing when you hovered over something interactive would have been appreciated. And the calibration puzzle took me a little but once I looked at the hint from a different angle, I literately facepalmed and felt so stupid. Finally was able to beat the game and although the toilet part frustrated me, it was a nice little puzzle game.