Steps I took that resulted in the problem:
I used the Radio Shack stripboard, then File > Export > as Image > svg
What I expected should have happened instead:
The vertical lines are too thin, much thinner than the pinhole diameter. Also, inside the pinholes, some solid stuffs occur.
My version of Fritzing and my operating system:
Fritzing 0.9.3.b
Linux Mint 17.3