Can’t create link on button

Hi,

When creating a button with Gutenberg editor the icon that allows to add a link is not display.

Check please this video where you will see 2 websites. The first one is where the problem is. The second one is fine.

https://www.loom.com/share/f124adf77afd42c388cdb3631d9dea0e

I deactivated plugins and updated the site but the problem is still there.

Could you please addvice?

Manu thanks