[Feature]: Observe onBlur events for text_extra

[federiva]

Guidelines

• [X] I agree to follow this project's Contributing Guidelines.

Description

There are some situations in which listening to the onInput event might be too verbose for an app. It would be great to have an onBlur observable event in a shiny app

Problem

We need an onBlur event to be observed in a Shiny app

Proposed Solution

Add onBlur event when creating the React element

Alternatives Considered

Add manually the event after rendering the component in the browser

[justacec]

What is the status here?! This has been here for a while and there is an associated PR for this with no feedback from the developers? I could have used this feature recently but had to adjust my internal data model to fit this with the per button press callback. (I am also suffering from the weird memory state issue when removing or adding rows to a table)