handle relative icon urls, fixes #1783
handle relative icon urls, fixes #1783
blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-browser,blockstack/blockstack-portal,blockstack/blockstack-browser