V9 Search box font size

Since upgrading to V9 the size of the font in the search box** has increased to such a size that it is unusable. I have looked within the theme for an appropriate font size setting and found nothing. Changing fonts under settings has no effect on the seach box, frankly I am stumped.

Any suggestions please

** this where as you type the email that you are searching for, a list of possibilities start to populate below the search field

What scaling are you using in your Windows display settings?

Just checked, set as default 100%