I could try. But I haven’t put anything new Add-on wise since forever, and ctrl f12 always worked.
I've replied basing on your report that GSX works normally from the menu, but not from the keyboard.
Addons do not control the keyboard directly ( at least, not proper ones, like GSX, others might do that ), they ASK the sim through Simconnect to let it use some key combination and the sim will then handle the actual keyboard handling. Which means, if any other addon has asked for the same hotkey, and it asked for exclusive use, and it asked before GSX ( depending on loading order ), the key GSX asked for won't work. If the other add-on didn't ask for exclusive use, they would both react to the same key at the same time.
That's why I'm telling you that, based on your report that GSX works from the menu, but not from the keyboard, the only possible explanation is another add-on taking that key.