For greater accessibility please add a text alternative to the standard popup ‘x’ close button. I suggest adding hidden/screenreader only ‘close’ text adjacent to the close image or adding an aria-label="Close’ to the button itself. Here a reference URL, aria-label - Accessibility | MDN. (aria-label - Accessibility | MDN)
Thank you for your assistance!
Folks, our former Wishlist portal, where our users shared their requests and suggestions, was transferred to this forum. You’re most welcome to vote, add new ideas, and leave your comments here — we surely will consider them all! 
Original Votes: 2
Hello,
Thank you for adding your idea and for the info provided!
We’ll try to think about this option in one of the future updates.
Thanks a lot for your help!
Helga, Community Manager
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Friends,
I’m happy to announce that keyboard navigation for close button is implemented! 
Now, you can close the widget with the help of Tab keys.
Feel free to check out this feature in our Popup online demo!