Using the Paint Bucket Tool multiple times darkens the fill color on the layer, and changing the selected color doesn't fill the layer with the new selected color but rather also darkens the existing one.

Reproducible: Always

Steps to Reproduce:
1.Select color
2.Select Paint Bucket Tool
3.Click on canvas or layer multiple times
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4.Change color
5. Click on canvas

Actual Results:  
1. First click  fills the layer with selected color, second click darkens it and so on until it's black.
2.After the second click fills the layer, changing the selected color doesn't fill the layer with that color but also heavily darkens it.

Expected Results:  
1.The layer should be filled with the selected color only,no matter how many times you click on it.
2. After changing the selected color, clicking on the layer should fill it with the new selected color.