My customer is complaining that SharePoint's built-in Rich Text Editor's paste button is disabled and copying/pasting only works via keyboard shortcuts Ctrl+C/Ctrl+V.
This happens on Chrome, Firefox and Edge browsers. However, on Internet Explorer the paste button works correctly.
I am quite sure that this is a known issue, and there is nothing that could be done to fix it (please correct me if I am wrong).
However, I have tried to search the internet for a definitive article explaining the problem. I could then show/quote this article to my customer, and have her then accept the current situation.
My question is:
Do you have any good pointers to articles/web sites that would explain the reason(s) for this problem:
Why the paste button works in IE, and why is it disabled in other browsers?