Make the screen NOT adjust the brightness?

[Hellishness]

The brightness goes up when you plug in your MBA, but then over time it just goes up and up. I honestly like my brightness pretty low (rarely more than half, typically at 3-5 notches), but it just keeps on going up and up. I almost never set it above half, but multiple times a day, I notice that it looks pretty high and it's at like 3/4 so I put it it down to about 1/3, but after a while, it's just up again.

Anyone else notice this? What is it, why does it do this? How can I fix it?
I don't mind not having auto-brightness (even though I loved it), as long as my screen doesn't keep going up.

 

[Fuchal]

The brightness goes up when you plug in your MBA, but then over time it just goes up and up. I honestly like my brightness pretty low (rarely more than half, typically at 3-5 notches), but it just keeps on going up and up. I almost never set it above half, but multiple times a day, I notice that it looks pretty high and it's at like 3/4 so I put it it down to about 1/3, but after a while, it's just up again.

Anyone else notice this? What is it, why does it do this? How can I fix it?
I don't mind not having auto-brightness (even though I loved it), as long as my screen doesn't keep going up.

It seems like a bug that it only goes up.

But you can disable it in Energy Saver preferences.