Window controls color faded

[chaushev]

So suddenly my default theme colors changed. Here is a crop from a screenshot before and after the problem occurred. I have tried various options in Unity tweak, reset unity, changed theme etc etc. Nothing seemed to work. Do you have any idea how can I resolve this issue? It is driving me crazy.
Before:
250839
After:
250840

[chaushev]

I have been searching the Internet but nothing came up...any ideas? Perhaps I need to reset the default theme somehow?