Assumingly such issues will also occur in OE Mobile: https://c.getsatisfaction.com/tiggzi/topics/mapping_arrows_are_not_showing_in_chrome_26
I was seeing this yesterday on Chrome and IE 10.
Progress is aware of the missing mapping arrows in Chrome. OpenEdge defect OE00234123 has been opened to track it. Thanks to all who reported the issue.
Roberta Miller
Progress Technical Support