Added native support for DualShock 4 controllers on Windows.
The version number (1.09) was added to the settings screen for easier verification. Context for GOG Users firewatch-gog-update-v1-09
While it is frequently associated with the Steam version, the changes listed for v1.09 (released in May 2018) included the following: Added native support for DualShock 4 controllers on Windows
Fixed a threading crash that occurred for some users on loading screens and resolved a framerate drop that happened when examining most objects. firewatch-gog-update-v1-09
Firewatch update primarily addressed stability and controller support, specifically introducing the ability to view the game's version number on the settings screen.
For those looking for help with modern issues, the GOG Community Forum remains the primary place for troubleshooting specific errors like black screens or save-load bugs.