Extended Reality (XR) is a rapidly growing field offering unique immersive experiences, social networking, learning, and collaboration opportunities. The continuous advancements in XR technology and industry efforts are gradually moving this technology toward end consumers. However, a universal one-size-fits-all solution for seamless XR interaction still needs to be discovered. Currently, we face a diverse landscape of interaction modalities that depend on the environment, user preferences, task, and device capabilities. Commercially available input methods like handheld controllers, hand gestures, voice commands, and combinations of those need universal flexibility and expressiveness. Additionally, hybrid user interfaces, such as smartwatches and smartphones as ubiquitous input and output devices, expand this interaction design space. In this position paper, we discuss the idea of a universal interaction concept for XR. We present challenges and opportunities for implementing hybrid user interfaces, emphasizing Environment, Task, and User. We explore the potential to enhance user experiences, interaction capabilities, and the development of seamless and efficient XR interaction methods. We examine challenges and aim to stimulate a discussion on the design of generic, universal interfaces for XR.