Seamonkey: "ReferenceError: structuredClone is not defined"
 

on jsx code:

This code works in Firefox, Chromium.

Seamonkey is not present in the Browser compatibility list:
https://developer.mozilla.org/en-US/...tructuredClone

Does it please mean this function is not supported in Seamonkey ?

The first question I would ask is whether it works in Seamonkey. Have you tried it?

I doubt anyone here can give a definitive answer as to why Seamonkey is not included in a list on the Mozilla website. You should direct that question to Mozilla.

I think it's fairly self-evident that yes, that means that that function is not supported in the version of seamonkey you tested with.

Get a polyfill. Or transpile it.

Yes I posted the result in the first post.

Thank you. I'm sorry seamonkey is not present in the Supported Browsers list https://polyfill.io/v3/supported-browsers

 

SeaMonkey uses Gecko - the same engine as Firefox.

As per the the SeaMonkey FAQ, the second digit in the version number corresponds to the Firefox version (with an offset of three), thus the current SeaMonkey 2.53.16 is equivalent to Firefox 56.

Thank you, Firefox 56 is pretty old and unsecure now. So current SeaMonkey is as secure as Firefox 56 ?

 

Security cannot be simplified to version numbers and age.

It is clear SeaMonkey makes regular releases and they explicitly state that they backport important fixes from newer Firefox versions.

The reason SeaMonkey is based on Firefox 56 is probably because Firefox 57 is when Mozilla introduced major changes with Quantum.

thank you.