vscode linux UI border menu has a white border

I am using Linux Ubuntu LTS 20.04 with BSPWM, SXHKD, PICOM, POLYBAR, on VMware Pro. When I click on any menu, it has a border around it that is white and a little blurry. How can I solve it? I want to delete it

I tried to modify picom but I can’t fix it

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