diff --git a/.circleci/config.yml b/.circleci/config.yml
index cd1428b86aeb4..dffff08b436fd 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -816,6 +816,7 @@ jobs:
             browser64_4gb.test_async_*
             browser64_4gb.test_audio_worklet*
             browser64_4gb.test_emscripten_log
+            browser64_4gb.test_clientside_vertex_arrays_es3
             "
   test-browser-firefox:
     executor: bionic
diff --git a/src/library_webgl.js b/src/library_webgl.js
index 9bcfc55921ef9..c4c507255a2c3 100644
--- a/src/library_webgl.js
+++ b/src/library_webgl.js
@@ -425,8 +425,8 @@ for (/**@suppress{duplicate}*/var i = 0; i < {{{ GL_POOL_TEMP_BUFFERS_SIZE }}};
     getSource: (shader, count, string, length) => {
       var source = '';
       for (var i = 0; i < count; ++i) {
-        var len = length ? {{{ makeGetValue('length', 'i*4', 'i32') }}} : -1;
-        source += UTF8ToString({{{ makeGetValue('string', 'i*4', 'i32') }}}, len < 0 ? undefined : len);
+        var len = length ? {{{ makeGetValue('length', 'i*' * POINTER_SIZE, '*') }}} : undefined;
+        source += UTF8ToString({{{ makeGetValue('string', 'i*' + POINTER_SIZE, '*') }}}, len);
       }
 #if LEGACY_GL_EMULATION
       // Let's see if we need to enable the standard derivatives extension
diff --git a/test/code_size/hello_webgl2_wasm.json b/test/code_size/hello_webgl2_wasm.json
index 3952a359b432a..708a528a29e1f 100644
--- a/test/code_size/hello_webgl2_wasm.json
+++ b/test/code_size/hello_webgl2_wasm.json
@@ -1,10 +1,10 @@
 {
   "a.html": 569,
   "a.html.gz": 379,
-  "a.js": 4697,
-  "a.js.gz": 2419,
+  "a.js": 4681,
+  "a.js.gz": 2412,
   "a.wasm": 10388,
   "a.wasm.gz": 6692,
-  "total": 15654,
-  "total_gz": 9490
+  "total": 15638,
+  "total_gz": 9483
 }
diff --git a/test/code_size/hello_webgl2_wasm2js.json b/test/code_size/hello_webgl2_wasm2js.json
index b517182ac5ead..823857f3e7a81 100644
--- a/test/code_size/hello_webgl2_wasm2js.json
+++ b/test/code_size/hello_webgl2_wasm2js.json
@@ -1,10 +1,10 @@
 {
   "a.html": 567,
   "a.html.gz": 379,
-  "a.js": 17931,
-  "a.js.gz": 8098,
+  "a.js": 17917,
+  "a.js.gz": 8089,
   "a.mem": 3123,
   "a.mem.gz": 2693,
-  "total": 21621,
-  "total_gz": 11170
+  "total": 21607,
+  "total_gz": 11161
 }
diff --git a/test/code_size/hello_webgl_wasm.json b/test/code_size/hello_webgl_wasm.json
index a8d0e016d22ea..1d73a396b7380 100644
--- a/test/code_size/hello_webgl_wasm.json
+++ b/test/code_size/hello_webgl_wasm.json
@@ -1,10 +1,10 @@
 {
   "a.html": 569,
   "a.html.gz": 379,
-  "a.js": 4183,
-  "a.js.gz": 2241,
+  "a.js": 4167,
+  "a.js.gz": 2236,
   "a.wasm": 10388,
   "a.wasm.gz": 6692,
-  "total": 15140,
-  "total_gz": 9312
+  "total": 15124,
+  "total_gz": 9307
 }
diff --git a/test/code_size/hello_webgl_wasm2js.json b/test/code_size/hello_webgl_wasm2js.json
index 171e6eea03c2f..cb6d778b2b99e 100644
--- a/test/code_size/hello_webgl_wasm2js.json
+++ b/test/code_size/hello_webgl_wasm2js.json
@@ -1,10 +1,10 @@
 {
   "a.html": 567,
   "a.html.gz": 379,
-  "a.js": 17409,
-  "a.js.gz": 7912,
+  "a.js": 17395,
+  "a.js.gz": 7900,
   "a.mem": 3123,
   "a.mem.gz": 2693,
-  "total": 21099,
-  "total_gz": 10984
+  "total": 21085,
+  "total_gz": 10972
 }