Brightness + Color effect doesn't work the same as Scratch 2

[paulkaplan]

Expected Behavior

Please describe what should happen
Scratch 2, if you set brightness effect to 100 and color effect to 50, this is what you get

Actual Behavior

Describe what actually happens

In Scratch 3, you get all white (I added a background so that you can see it).

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This bug is a simplification of a problem I had when opening this project in scratch 3 https://scratch.mit.edu/projects/1270935/
It should look like this

And instead looked like this

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cc @cwillisf

[BryceLTaylor]

I'm still seeing some strangeness with Brightness but it's a little different from what's listed above. It looks like project 1270935 is working properly. Also, brightnesses between -100 and 0 are behaving as expected.

For brightnesses between 0 and 100 it looks like it is getting brighter, but not all the way white as it does in 2.0.

Here it is in 2.0:

And here it is in 3.0:

I used this project: https://scratch.mit.edu/projects/276912470/ to test this.