StyledText does not restore default line height on setText() if increased by previous content

[tmssngr]

Describe the bug
A StyledText increases automatically the line height if the default font can't display some characters and another, larger replacement font is used. That is more or less reasonable. However, when setting a new text, it should reset the line height to the default value.

To Reproduce

import org.eclipse.swt.*;
import org.eclipse.swt.custom.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class StyledTextLineHeightTest {

	public static void main(String[] args) {
		final Display display = new Display();

		final Font font = new Font(display, "Ubuntu Mono", 10, 0);

		final Shell shell = new Shell(display);
		shell.setLayout(new GridLayout(2, true));

		final StyledText text = new StyledText(shell, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL);
		text.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1));
		text.setFont(font);

		createButton("Set US-Ascii Text", shell)
				.addListener(SWT.Selection, e -> {
					text.setText("""
					             line 1
					             line 2
					             line 3
					             line 4
					             """);
				});
		createButton("Set Non-US-ASCII Text", shell)
				.addListener(SWT.Selection, e -> {
					text.setText("""
					             नमस्ते। आप कैसे हैं?
					             こんにちは。お元気ですか？
					             안녕하세요. 잘 지내시나요?
					             Γεια σου. Τι κάνεις;
					             """);
				});

		shell.setSize(400, 300);
		shell.open();

		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) {
				display.sleep();
			}
		}

		font.dispose();

		display.dispose();
	}

	private static Button createButton(String text, Shell shell) {
		final Button button = new Button(shell, SWT.PUSH);
		button.setText(text);
		button.setLayoutData(new GridData(SWT.FILL, SWT. FILL, false, false));
		return button;
	}
}

• click the "Set US-Ascii Text" button -> the text is displayed with default line height
• click the "Set Non-US-ASCII Text" button -> the line height increases (mostly noticeable on Linux)
• click the "Set US-Ascii Text" button again -> the increased line height remains

Expected behavior
The line height for new texts should be as for a new StyledText control, not influenced by previous text content.

Screenshots
After clicking "Set US-Ascii Text" button:

After clicking "Set Non-US-ASCII Text" button:

After clicking "Set US-Ascii Text" button again:

Environment:

1. Select the platform(s) on which the behavior is seen:

• • All OS
• • Windows
• • Linux
• • macOS

Workaround (or) Additional context
Create a new StyledText control before setting the next text (not always an easy option).