Hello,
I did all right and sucess with 2 masks
I got an issue when I did 3 masks … how can I fix … or it is working up to 2 mask only?
It does not have black background … it is a white background as inside of masks 
imposto de renda.mlt (45.9 KB)
thanks in advance for any help !
Multiple masks is not supported. See here for details:
For complex masks, use Mask: Draw (Glaxnimate)
You can use Mask: Simple Shape multiple times as you have done. You just cannot use Mask: Apply multiple times. I do not see the problem you are trying to describe. What you have setup is to blur inside of 3 rectangles.
It does not have black background
A mask does not create a black background (black outside of the mask).
Your third mask blurs something that does not have much detail. Here is an example using Invert Colors to make it more obvious:
Yes, I was surprised to see that.
I often combine multiple Mask filters to create masks of somewhat complex shapes. Or to highlight or blur multiple regions on the screen.
If you want only black outside the mask, you can composite over a color clip. As a reminder, things do not composite/blend with a hidden black background; you need to specify it.
I need to hide personal informations I don’t want to be public 
so nice this video man … publish it ! or where was published ?
I want exactly opposite of a black background … I just want to blur personal information and make visible everything outsite of the mask …
An easier method is the Spot remover filter. If that works for your needs you don’t need to deal with complicated masks.
Daniel
thanks for you help … I feel it works to what I want to do …
tested and it is fine to me and my video
