--- a/dom/canvas/WebGLShaderValidator.cpp	2017-04-11 04:13:14.000000000 +0200
+++ b/dom/canvas/WebGLShaderValidator.cpp	2017-10-18 21:37:05.383873927 +0200
@@ -114,7 +114,7 @@
         case 440: return SH_GLSL_440_CORE_OUTPUT;
         case 450: return SH_GLSL_450_CORE_OUTPUT;
         default:
-            MOZ_CRASH("GFX: Unexpected GLSL version.");
+            MOZ_ASSERT(false, "GFX: Unexpected GLSL version.");
         }
     }