Font Size Combobox Test

Test Instructions:

• Type a custom font size: Click on the font size input, type a value like "15pt" or "22pt", and press Enter
• Type just numbers: Type "20" and press Enter - it will automatically add "pt" to make it "20pt"
• Select from dropdown: Click on the input and select a predefined size from the dropdown list
• Mix units: Try typing "1.5em", "18px", or "150%" to see various CSS units work
• Current size display: Select some text and notice the placeholder shows the current font size