WinForms Example - Find not correctly selecting next match.

### Is there an existing issue for this?

- [X] I have searched both open/closed issues, no issue already exists.

### CefSharp Version

113.1.4

### Operating System

Windows 11

### Architecture

x86

### .Net Version

4.8

### Implementation

WinForms

### Reproduction Steps

- Open any PDF file in the browser with "file:///"
- In the WinForms.Example application click on Edit->Find
- Enter text in the TextBox and hit Enter
--> Find(...) method will be executed and found results are marked in the scroll bar at the side
--> Matching text will not be highlighted and "Find Next", "Find Previous" buttons won't do anything visible to the user (they also do not seem to do from HTML pages)

### Expected behavior

Matching content is highlighted (like it is for HTML documents) and the browser scrolls to make the match visible, if not currently visible.

### Actual behavior

Matches are only indicated in the scroll bar but no highlighting is visible.

### Regression?

_No response_

### Known Workarounds

_No response_

### Does this problem also occur in the CEF Sample Application

No

### Other information

Not sure if it is a CefSharp or a CEF issue. The CEF sample application behaves a bit better, but has a different search dialog compared to the WinForms Example that comes with CefSharp.