Trying to inserting emoji via LaunchBar replaces text in shape instead

# Repro

## Setup

macOS with LaunchBar installed.

## Steps

1. Add a shape to a Lucidspark board.
2. Double-click the shape to edit its text.
3. Type some text but don’t press return yet (so that the system caret is still positioned at the end of the text inside the shape).
4. Activate LaunchBar, navigate to an emoji (e.g., 👋) and press return to insert it.

## Expected behaviour

The emoji is appended to the end of the text (e.g., “Hello world 👋”).

## Actual behaviour

The text in the shape is replaced by a couple of black bars.

## Screenshots

Here’s what the shape looks like before trying to insert an emoji using LaunchBar (vertical black line is the system caret):

Here’s what the shape looks like after trying to insert any emoji using LaunchBar:

# Additional notes

Inserting an emoji using LaunchBar works as expected in other applications (including this form 😇).