Struggling with EXT_multisampled_render_to_texture on Mali-G76

Just for reference, here's a patch on top of the gles3jni example from https://github.com/android/ndk-samples (the same type of code works for the hello-gl2 sample as well) demonstrating how to load the right function pointers, plus how using the non-EXT glRenderbufferStorageMultisample can result in this error (see the #if for good vs non-working code):

diff --git a/gles3jni/app/src/main/cpp/RendererES3.cpp b/gles3jni/app/src/main/cpp/RendererES3.cpp
index df71a85..c7366a5 100644
--- a/gles3jni/app/src/main/cpp/RendererES3.cpp
+++ b/gles3jni/app/src/main/cpp/RendererES3.cpp
@@ -15,6 +15,8 @@
  */
 
 #include "gles3jni.h"
+#include <GLES2/gl2ext.h>
 #include <EGL/egl.h>
 
 #define STR(s) #s
@@ -117,6 +119,55 @@ bool RendererES3::init() {
     glVertexAttribPointer(OFFSET_ATTRIB, 2, GL_FLOAT, GL_FALSE, 2*sizeof(float), 0);
     glEnableVertexAttribArray(OFFSET_ATTRIB);
     glVertexAttribDivisor(OFFSET_ATTRIB, 1);
+#if 1
+       GLsizei width  = 256;
+       GLsizei height = 256;
+       GLint samples;
+       glGetIntegerv(GL_MAX_SAMPLES_EXT, &samples);
+
+    PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXTPROC glRenderbufferStorageMultisampleEXT =            (PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXTPROC)eglGetProcAddress("glRenderbufferStorageMultisampleEXT");
+    PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEEXTPROC glFramebufferTexture2DMultisampleEXT =(PFNGLFRAMEBUFFERTEXTURE2DMULTISAMPLEEXTPROC)eglGetProcAddress("glFramebufferTexture2DMultisampleEXT");
+
+       /* Create multisampled depth renderbuffer */
+       GLuint depthbuffer;
+       glGenRenderbuffers(1, &depthbuffer);
+       glBindRenderbuffer(GL_RENDERBUFFER, depthbuffer);
+#if 0 // OK
+       glRenderbufferStorageMultisampleEXT(GL_RENDERBUFFER, samples, 
+               GL_DEPTH_COMPONENT16, width, height);
+#else // Fails
+       glRenderbufferStorageMultisample(GL_RENDERBUFFER, samples, 
+               GL_DEPTH_COMPONENT16, width, height);
+#endif
+       glBindRenderbuffer(GL_RENDERBUFFER, 0);
+
+       /* Create RGBA texture with single mipmap level */
+       GLuint texture;
+       glGenTextures(1, &texture);
+       glBindTexture(GL_TEXTURE_2D, texture);
+       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, 
+               GL_UNSIGNED_SHORT_4_4_4_4, NULL);
+       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+       glBindTexture(GL_TEXTURE_2D, 0);
+
+       /* Create framebuffer object, attach texture and depth renderbuffer */
+       GLuint framebuffer;
+       glGenFramebuffers(1, &framebuffer);
+       glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
+       glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, 
+               GL_RENDERBUFFER, depthbuffer);
+       glFramebufferTexture2DMultisampleEXT(GL_FRAMEBUFFER, 
+               GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0, samples);
+
+       /* handle unsupported cases */
+       if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != 
+                       GL_FRAMEBUFFER_COMPLETE)
+       {
+        ALOGE("FBO incomplete: %x", glCheckFramebufferStatus(GL_FRAMEBUFFER));
+       } else ALOGE("FBO OK");
+
+    checkGlError("FBO");
+#endif
 
     ALOGV("Using OpenGL ES 3.0 renderer");
     return true;

It might be good to double-check any function pointer loader you might be using isn't grabbing the wrong function.