Found this small issue when Firefox updated to Version 112. This is on a Mac running Ventura 13.13.1. My Windows 11 and Linux (Fedora) updates did not show this.
That's strange! Normally the fonts are all the same size and everything is in proportion. Do you notice any other dialogs where some controls are oversized compared with others, or where the right side is cut off?
No other dialogs show this behavior. And note that the dialog is different when there is an open tab and no open tabs. Font size, spacing, and buttons are different.