Skype 8 icon in notification area

As I wrote before, finally I had to update to Skype 8. I was experiencing strange glitches and at the end I was forced to update. It still looks extremely bad but couple of most annoying issues was fixed.

But today I want to talk about Skype icon in notification area. After some time after I did upgrade on my home computer, I did notice strange empty space as shown on picture below:

After some time, I did realize that it is actually Skype that lost its icon. Strange but well and I did restart Skype. After some time, icon did disappear again. Then I did realize that icon did disappear on my work computer:

And then I did realize that:

1. I never seen it on old Skype even I used it like 10 years
2. I probably seen it once before from time when notification area was introduced in Windows 95 and I’m pretty sure it was application that I was developing, and I simply did something incorrectly.
3. I asked people around and pretty much every single one seen the same problem

And it leads me to conclusion: How bad are actually developers that develop Skype that even so simple task as setting icon in notification area they did wrong?