While running Dragonruby, I didn't want to use my touchpad so I hit the key to toggle it off, causing the following error:
ERROR: Attempted to set the structure, but the property isn't available. You should contact DragonRuby and tell them to add this key to the @char_to_method hash. [KeyboardKeys#set, DragonRubyView#char_to_method]
And then said it printed the game state to "game_state_872.txt", which I only mention because it didn't actually do that at all, there is no .txt under that name, despite it easily making many other such .txt files.
To try and give info that might help:
I'm running 64bit Windows 10 on a Lenovo Yoga 710-15, the touchpad being listed as a "Synaptics ClickPad v1.6 on SMB Port" in the device settings, using driver version "220.127.116.11". With my configuration I have to press fn+f6 to toggle the touchpad, that combo is causing the issue. The other keys functions I have to use fn for do not cause this issue, nor does f6 on its own.
Hopefully that helps, this didn't really impede my day much, but I figured I should report it.