### .NET version 10.0.100-alpha.1.24553.6 ### Did it work in .NET Framework? No ### Did it work in any of the earlier releases of .NET Core or .NET 5+? No, all versions have this issue ### Issue description Pressing Up/Down keyboard in drop-down list of property collapses dropdown directly.  **Expand Result**: Drop-down list keeps expanding state when pressing Up/Down keyboard, then pressing Enter can collapse it ### Steps to reproduce Repro steps: 1. Find one property with dropdown list in PropertyGrid, for example: **Multiline** 2. Tab to its value part: **False**, then press Up keyboard to change value: **True** --- it is necessary step 3. Press Alt+Down or F4 to expand this property's drop-down list 4. Press Down keyboard to choose another value: **False**