dont attempt to overwrite RTCSessionDescription.sdp

follow-up on #1042
webrtcHacks · Mar 10, 2021 · de0348c · de0348c
1 parent 0656728
commit de0348c
Showing 1 changed file with 11 additions and 1 deletion.
diff --git a/src/js/common_shim.js b/src/js/common_shim.js
@@ -331,9 +331,19 @@ export function removeExtmapAllowMixed(window, browserDetails) {
   window.RTCPeerConnection.prototype.setRemoteDescription =
   function setRemoteDescription(desc) {
     if (desc && desc.sdp && desc.sdp.indexOf('\na=extmap-allow-mixed') !== -1) {
-      desc.sdp = desc.sdp.split('\n').filter((line) => {
+      const sdp = desc.sdp.split('\n').filter((line) => {
         return line.trim() !== 'a=extmap-allow-mixed';
       }).join('\n');
+      // Safari enforces read-only-ness of RTCSessionDescription fields.
+      if (window.RTCSessionDescription &&
+          desc instanceof window.RTCSessionDescription) {
+        arguments[0] = new window.RTCSessionDescription({
+          type: desc.type,
+          sdp,
+        });
+      } else {
+        desc.sdp = sdp;
+      }
     }
     return nativeSRD.apply(this, arguments);
   };