Problems with Chrome and Windows 10
Really liked f.lux for each computer I've used it on, except this newest one (Lenovo Yoga 910). F.lux was one of the first things I downloaded from the Windows Store and works as it should except when I have Chrome open. The window for Chrome will be the normal brightness level while the rest of the screen (if I have multiple windows open) will be adjusted by f.lux. If I move between two Chrome windows, whichever is selected will be the normal brightness but the other will be adjusted. If I go fullscreen for a youtube video it will be unadjusted. Hoping this can be fixed with a patch.
It sounds to me like you have the beta version of f.lux and somehow have disabled it for both full screen applications and for that one instance of Chrome.
Whenever f.lux has been disabled for a specific program, the only way to undo the disabling is by putting that program/window in focus and then opening the f.lux menu. So whichever window or program was last in focus before opening the f.lux menu determines which program f.lux will be focused on for the feature of disabling for specific programs.
We heard this several times about this Lenovo model last year.
I believe it has an Intel integrated GPU and an NVIDIA discrete one.
Unfortunately, one of the drivers (I believe Intel) has been held back by Lenovo, so the two GPUs are not working well together.
If you can manually update your GPU drivers so they are both current (from this year), it will likely fix the issue.
Try to run "Device Manager" and see which GPU drivers are there (i.e. the date they were published), and try to download an update.