I've been searching forever and I can't seem to find anything like it, but that might be because I'm not good with plants.
It's difficult for me to determine what I need to see because of the very busy background.
Is it possible to dig out the plant and isolate it on the sidewalk or other plain background?
It does look very hard to recognise. It does remind me of spurge, but given the lack of clarity in the photo, as jean said, it's a tough call.