Premiere – ‘Composite in Linear Color’ breaks dissolve transitions?..

Software:
Premiere Pro CC 2018

I was baffled,
Not understanding why my dissolve transitions in a new Premiere project are not linear, and too lift too fast,
I validated this in the Lumetri Scopes window.
In an older project, at 50 percent transition duration, white color is at 50 percent intensity like you’d expect from a linear transition.
But in my new project, at 50 percent transition duration, white color is at about 75 + percent intensity as if it’s gamma corrected.

Solution:
After some web research in discussion groups, I found that the option that doe’s that is:
Sequence Settings > Composite in Linear Color
And unchecking it solves the problem.

It’s still weird to me that¬†Composite in Linear Color¬†breaks the linearity of the dissolve transition,
But at least there is a solution.

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