deleting brushes
1. Open photoshop and click on the brush tool or simply type b on your keyboard.
2. Now on your top-left hand side it says brush, click on that and you'll see a little arrow next to it. Now click on that and you'll see a big thing pop up, click on the preset manager.
3. Here you can select one brush by just clicking on it, or click on one then pres shift + up/down/left/right to select more than one brush.
4. Now click on delete.
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