diff --git a/Libraries/LibWeb/WebGL/WebGL2RenderingContextBase.idl b/Libraries/LibWeb/WebGL/WebGL2RenderingContextBase.idl
index bf3fd7154dd..21c8d2f1075 100644
--- a/Libraries/LibWeb/WebGL/WebGL2RenderingContextBase.idl
+++ b/Libraries/LibWeb/WebGL/WebGL2RenderingContextBase.idl
@@ -323,7 +323,7 @@ interface mixin WebGL2RenderingContextBase {
     // May throw DOMException
     [FIXME] undefined texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, TexImageSource source);
 
-    [FIXME] undefined texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, [AllowShared] ArrayBufferView? srcData, optional unsigned long long srcOffset = 0);
+    undefined texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, [AllowShared] ArrayBufferView? srcData, optional unsigned long long srcOffset = 0);
 
     [FIXME] undefined copyTexSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLint x, GLint y, GLsizei width, GLsizei height);
 
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWebGLRenderingContext.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWebGLRenderingContext.cpp
index e7f954d0e9d..922d23dddcd 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWebGLRenderingContext.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWebGLRenderingContext.cpp
@@ -670,6 +670,19 @@ public:
             continue;
         }
 
+        if (function.name == "texSubImage3D"sv && function.overload_index == 0) {
+            function_impl_generator.append(R"~~~(
+    void const* pixels_ptr = nullptr;
+    if (src_data) {
+        auto const& viewed_array_buffer = src_data->viewed_array_buffer();
+        auto const& byte_buffer = viewed_array_buffer->buffer();
+        pixels_ptr = byte_buffer.data() + src_offset;
+    }
+    glTexSubImage3D(target, level, xoffset, yoffset, zoffset, width, height, depth, format, type, pixels_ptr);
+)~~~");
+            continue;
+        }
+
         if (function.name == "getShaderParameter"sv) {
             function_impl_generator.append(R"~~~(
     GLint result = 0;