Hundreds of millions of speakers of bidirectional (BiDi) languages rely on writing systems that mix the native right-to-left script with left-to-right strings. The global reach of interactive digital technolo-gies requires special attention to these people, whose perception of interfaces is afected by this script mixture. However, empirical research on this topic is scarce. Although leading software ven-dors provide guidelines for BiDi design, bidirectional interfaces demonstrate inconsistent and incorrect directionality of UI ele-ments, which may cause user confusion and errors. Through a websites' review, we identifed problematic UI items and considered reasons for their existence. In an online survey with 234 BiDi speakers, we observed that in many cases, users' direction preferences were inconsistent with the guidelines. The fndings provide potential insights for design rules and empirical evidence for the problem's complexity, suggesting the need for further em-pirical research and greater attention by the HCI community to the BiDi design problem.