How to copy text from my web game that I hosted on Itch.io?

I am having trouble copying specific text to the clipboard in a game I developed in Unity that I am hosting directly in the browser on Itch.io.

The code I implemented works perfectly in the editor and when I run the application using Visual Studio Code (Live Server), but never in the application hosted on the Itch.io website.

I want to emphasize that I am not violating any Itch.io guidelines. In fact, I was able to copy texts from other games, most of which were made in Python (mainly visual novels) and one in Scratch. I searched for several games developed in Unity, but none of those I found had any visible input fields or text chat, and given the sampling, I found that sufficient.

Below are two screenshots proving that it is possible to copy:

Initially, I tried passing the text that I wanted to be sent to the clipboard in a method that was called upon clicking a button.

Code.cs:

#if UNITY_WEBGL && !UNITY_EDITOR
using System.Runtime.InteropServices;
#endif

//usings and class declaration...

#if UNITY_WEBGL && !UNITY_EDITOR
    [DllImport("__Internal")]
    static extern void CopyToClipboard(string copyText);
#endif

    public void WordToGepeto()
    {
        string _word = "";
        
        //logic...

        _word = _word.TrimEnd();
        CopiarParaClipboard(_word);
    }

    public void CopiarParaClipboard(string _texto)
    {
#if UNITY_WEBGL && !UNITY_EDITOR
        CopyToClipboard(_texto);
#else
        GUIUtility.systemCopyBuffer = _texto;
#endif
    }

Code.js (inside the Plugins folder located in Assets):

mergeInto(LibraryManager.library, {
    CopyToClipboard: function(copyText) {
        var text = UTF8ToString(copyText);
        navigator.clipboard.writeText(text).then(function() {
            console.log('Texto copiado para a área de transferência com sucesso!');
        }).catch(function(error) {
            console.error('Falha ao copiar texto: ', error);
        });
    }
});

This was the error that appeared:

[Violation] Permissions policy violation: The Clipboard API has been blocked because of a permissions policy applied to the current document. See https://sites.google.com/a/chromium.org/dev/Home/chromium-security/deprecating-permissions-in-cross-origin-iframes for more details.

Forca.framework.js:3 Falha ao copiar texto:  NotAllowedError: Failed to execute 'writeText' on 'Clipboard': The Clipboard API has been blocked because of a permissions policy applied to the current document. See https://sites.google.com/a/chromium.org/dev/Home/chromium-security/deprecating-permissions-in-cross-origin-iframes for more details.

The link does not lead anywhere (Error 404).

After that, I tried to modify the iframe, but it's only possible to read it.

Later, I gave up using a button and created an InputField to manually copy the text (using control + c). To my complete surprise, even that didn’t work. No error appears, it just doesn’t copy.

Below are other things I tried before coming to ask for help:

• I changed the Unity version (from 2020.3.37f1 to 2021.3.18f1).

• I tried adding this code (<meta http-equiv="Permissions-Policy" content="clipboard-write=(self)">) in the header of the index.html file in the build.

• I switched browsers (I tried Edge, as I was previously using Chrome), and it presented the same error that was appearing before.

In a final attempt, I tried changing the Chrome settings, trying to force access to the clipboard (see image below), and even disabling its default protection, but nothing worked.

I will be immensely grateful for any help provided.