Making sure you're using Chrome, head over to the signup domain step (at https://wordpress.com/start), enter a search query, then attempt to place your cursor somewhere in the text field value.
The rebellious cursor won't go where you want it to go!
It seems to be due to adding a CSS height value to an input type="search" field.
As far as I can tell, this is only occurring in Chrome (not Canary)
I've confirmed this behaviour on several computers. See: https://jsfiddle.net/mn96k3dh/3/
Possible remedies:
textThe cursor would land where I click within the text
The cursor either inaccurately lands somewhere in the text string or remains at the end of the field
Chrome 77

Hey, I can fix this.
It looks like it's been fixed in Chromium (Build 78), though I have no clue how.
Is it correct that this is fixed again? I can't reproduce the problem in Chrome myself.
I can't reproduce this in Chrome 78. I think whatever bug was present was fixed on Chrome's end in recent updates.
Most helpful comment
Hey, I can fix this.