diff --git a/include/rfb.js b/include/rfb.js
index 00fb7d88..2a321d24 100644
--- a/include/rfb.js
+++ b/include/rfb.js
@@ -1252,11 +1252,11 @@ encHandlers.HEXTILE = function display_hextile() {
             rQi += FBU.bytes - 1;
         } else {
             if (FBU.subencoding & 0x02) { // Background
-                FBU.background = rQ.slice(rQi, rQi + fb_Bpp);
+                FBU.background = rQ.subarray(rQi, rQi + fb_Bpp);
                 rQi += fb_Bpp;
             }
             if (FBU.subencoding & 0x04) { // Foreground
-                FBU.foreground = rQ.slice(rQi, rQi + fb_Bpp);
+                FBU.foreground = rQ.subarray(rQi, rQi + fb_Bpp);
                 rQi += fb_Bpp;
             }
 
@@ -1266,7 +1266,7 @@ encHandlers.HEXTILE = function display_hextile() {
                 rQi += 1;
                 for (s = 0; s < subrects; s += 1) {
                     if (FBU.subencoding & 0x10) { // SubrectsColoured
-                        color = rQ.slice(rQi, rQi + fb_Bpp);
+                        color = rQ.subarray(rQi, rQi + fb_Bpp);
                         rQi += fb_Bpp;
                     } else {
                         color = FBU.foreground;
diff --git a/include/util.js b/include/util.js
index 57ccb540..030afb41 100644
--- a/include/util.js
+++ b/include/util.js
@@ -18,6 +18,10 @@ var Util = {};
  * Make arrays quack
  */
 
+Array.prototype.subarray = function (start, end) {
+    this.slice(start, end);
+};
+
 Array.prototype.push8 = function (num) {
     this.push(num & 0xFF);
 };