Steps to Reproduce

1. create a new book
2. input abc at A1
3. select A1
4. enlarge the formula bar's height

alternative steps

1. create a new book
2. input abc at A1
3. enlarge the formula bar's height
4. select A1

Current Result

formula bar's content is empty

Expected Result

formula bar contains A1's value abc

Workaround

press F2