I don't look for graphic resources super frequently as I'm more on the coding than the graphic making side but I use tchai.carrd.co (https://tchai.carrd.co/#masks) for masks, some yandex album hoards for transparents and overlays( https://docs.google.com/document/u/0/d/1S-Pb_jekl5G3VSI-YdZfuQiuVJ1DarEA0w4BMC9LF3Q/mobilebasic), and whatever pixel sites I can find basically but I gravitate towards pixels.crd.co (https://pixels.crd.co/#pixels)