I think you want to right click on the Fireworks shortcut icon and choose Compatability => Change High DPI Settings ... then choose override high DPI settings and select 'system' .... See screenshots:
Unfortunately, CS6 has not been updated since 2012 and is NOT HiDPI aware, nor will it ever be. Suggest you adjust your display's Scale and Layout from Windows System Settings (see screenshot).
NOTE 1: Increasing scale beyond 100% (normal) could result in some panels becoming truncated or clipped. Adjust accordingly.
NOTE 2: Using discontinued software is at your own risk. For best results, use modern software (Photoshop or Illustrator) that's no more than 2 versions back because it's more compatible with modern equipment.
The device probably has display scale for a reason, and changing it will likely not be helpul .... I've already given an explanation of how to change the High DPI settings of Fireworks.
I think you want to right click on the Fireworks shortcut icon and choose Compatability => Change High DPI Settings ... then choose override high DPI settings and select 'system' .... See screenshots: