https://bugs.freedesktop.org/show_bug.cgi?id=101325 --- Comment #13 from Julien Isorce --- apitrace dump: 94 glShaderSource(shader = 2, count = 2, string = {"#version 150 #define PLATFORM_USES_ES2 0 #define PLATFORM_LINUX 1 ", " #if PLATFORM_USES_ES2 precision highp float; #else // #version 120 at the beginning is added in FSlateOpenGLShader::CompileShader() #extension GL_EXT_gpu_shader4 : enable #endif varying vec2 textureCoordinate; uniform sampler2D SplashTexture; void main() { // OpenGL has 0,0 the \"math\" way vec2 tc = vec2(textureCoordinate.s, 1.0-textureCoordinate.t); gl_FragColor = texture2D(SplashTexture, tc); }"}, length = NULL) So it does not look that GL_EXT_gpu_shader4 is really used. Also I wonder if you can configure UE4Editor to use egl/gles2 and see if it still hangs. -- You are receiving this mail because: You are the assignee for the bug.