If you hover to a tab while typing in the address bar, wait for the pop-up menu with the tab address, and then try to enter the character again, the character is entered, but then the focus of the address bar disappears and you have to click on the address bar again. This definitely wasn't the case before, it appeared in one of the latest updates.
OS: Windows 10
Opera: 122.0.5643.51
The screenshot shows the pop-up menu of the tab, as well as the carriage in the address bar. If I enter any character at this point, it will be displayed, but the carriage will disappear.