Fix download image location
Fix download image location

macOS Catalina issue
https://forums.cocoaforge.com/viewtopic.php?t=27156
ViennaRSS/vienna-rss,barijaona/vienna-rss,josh64x2/vienna-rss,barijaona/vienna-rss,josh64x2/vienna-rss,barijaona/vienna-rss,ViennaRSS/vienna-rss,Eitot/vienna-rss,josh64x2/vienna-rss,josh64x2/vienna-rss,Eitot/vienna-rss,ViennaRSS/vienna-rss,ViennaRSS/vienna-rss,josh64x2/vienna-rss,barijaona/vienna-rss,Eitot/vienna-rss,barijaona/vienna-rss,Eitot/vienna-rss,ViennaRSS/vienna-rss