I want the opacity to stay the same on two overlapping strokes

https://imgur.com/pfffKXB.png

The first figure demonstrates the behavior i want the brush to have when two brush strokes overlap each other.

You can see in figure 2 that the opacity of the area where two brush strokes overlap is much more than in figure 1, and i don’t want that.

Does anybody have a way to “fix” this ?

I’m also wondering if this is the right category to ask this question so feel free to tell me where i should post this preferably.