On Jun 9, I copied this problem from Facebook and posted in WeChat group, with the following original hint:
Berger, 1888 white to move and win. (#16)
Jun 13, I re-posted the problem. I suggested another approach and drew an illustration diagram, but it ended up with question what can we do after Qf4 Ba6?
Jun 21, I asked again. No response.
July 4, I exclaimed that the problem is so hard. After 15 minutes, I claimed I had another solution, but again I found some small holes. The problem is put on backburner again.
July 26, I asked again. Another expert made another suggestion, with no confirmation from anyone.
Nov 22, 4 months later. I re-posted the problem. The same expert made couple suggestions, and some seemed to be positive progress.
Last night, Nov 25, when I woke up in the mid-night. The problem suddenly comes into my mind, and I knew I could solve it. I spent about half hour to solve it completely in my mind. Then fell into sleep again.
Finally, after 5 months 16 days, we have the solution!!!
I will explain the solution in my YouTube channel.