Secure Input stuck after High Sierra installation

I installed High Sierra on my MacBook Air last night, and since then Secure Input has been set on an eternal on state! (stuck)

I have no clues how to disable this, as it's affecting my experience on various apps like aText, Keyboard Maestro and many more.

This is similar to what happened here: How can I disable Secure Input when it is 'stuck'?

Any clues on how I can disable this completely/get it to the state it was on when I was on Sierra?