WPF - Html dropdown goes off screen when near bottom of page

- **What version of the product are you using?**
Myget, CefSharp.Wpf, 75.0.110-CI3174

- **What architecture x86 or x64?**
x64

- **On what operating system?**
Win10

- **Are you using `WinForms`, `WPF` or `OffScreen`?**
WPF

- **What steps will reproduce the problem?**
1. Clone https://github.com/Dumpen/CefSharp.MinimalExample
2. Set CefSharp.MinimalExample.Wpf and WebApplication1 as start up projects
3. Start it

- **What is the expected output? What do you see instead?**
The dropdown should be above the select input, but it is below

- **Please provide any additional information below.**
See image [here](https://i.ibb.co/pQZQ5th/ss.jpg). In a normal browser the dropdown is either above the select input or above the whole window if there is no space.

- **Does this problem also occur in the `CEF` Sample Application from http://opensource.spotify.com/cefbuilds/index.html?**
No, see https://i.ibb.co/nwC1nsN/ss2.jpg. I tested with cef_binary_75.0.11+gf50b3c2+chromium-75.0.3770.100_windows64_client.tar