Selection is empty when sliding to select a custom inline element such as a button; expected to be the currently selected element

[daifuyang]

Description
A clear and concise description of what the bug is.

Recording
https://app.screencastify.com/v3/watch/8iWG7Ab65tvhZ6AG28ay

Sandbox
https://codesandbox.io/p/sandbox/nxlvks

Steps
To reproduce the behavior:

1. Slide to select element
2. Click to get selection
3. Trigger null

Using the keyboard to move the cursor to select will not return null. Press shift + right

Expectation
Returns the correct selection of the element and can update custom values

Environment

• Slate Version: [0.112]
• Operating System: [macos]
• Browser: [Chrome 132.0.6834.160]
• TypeScript Version: [5.7.2]

Context
Thank you very much for your contribution