Right-click menu blurs focus; incorrect formatting

[jgranick]

https://github.com/user-attachments/assets/85876c4c-4963-4c06-8c87-3ef3a08d8bf4

Here are the steps to reproduce:

1. Right-click on a MathField element a. Important: The mouse must be over existing equation text
2. Select an option

Result:

The MathField will lose focus. If the option chosen changes the rendering, such as changing a color, then the rendering of the field may be incorrect.

Notes:

Right-clicking elsewhere on the field keeps the focus on the MathField. This issue occurs only if the right-click occurred on formatted text.