Follow these steps for 2560*1080:
- Open the exe file (BlackMirror.exe) with a hex editor.
- Replace all occurences of the hex values 39 8E E3 3F with 26 B4 17 40 (4 occurences)
- Save the exe, start the launcher, choose 2560*1080 in the dropdown menu.
- Badaboom! Glorious 21:9!
If you need another resolution, you have to calculate the values yourself:
- Calculate width / height (example: 2560/1080)
- Use a website to convert float to hex (2560/1080 = 2.37037037037 = 0x4017b426)
- Swap the byte order (0x4017b426 = 26 B4 17 40)
- Follow the instructions above with your individual hex values
I just did this a minute ago. So i don't know yet if there will be any issues. I wish the devs would just implement it themselves. It really isn't that hard. I did it by only changing a few bytes. For them it's probably just 2 lines of code to achieve the same thing.