Hey , after some testing it seems like the global clipping plane which is used for planar reflections does not work under OpenGL (can be seen on Windows as well when running standalone with -opengl). To test this you simply need to place a static mesh under a planar reflection actor with a transparent material and notice how the static mesh gets reflected even though it is on the wrong side or the reflection actor. Pretty much the same issue as Planar reflection clipplane bug on Metal - Platform & Builds - Epic Developer Community Forums but only for OpenGL