codeArea.getVisibleParagraphs() find lost some line

[xiaofanku]

I use java KeywordsDemo. Start filling the content area with empty content. Then copy a long piece of code and paste it into the codeArea, printing the parameters of the computeHighlighting method and finding that there is a behavior of missing lines. Only a few more scrolls will work properly。

like this:

[Jugen]

The problem is most likely in this section of code:

        public void accept( ListModification<? extends Paragraph<PS, SEG, S>> lm )
        {
            if ( lm.getAddedSize() > 0 ) Platform.runLater( () ->
            {
                int paragraph = Math.min( area.firstVisibleParToAllParIndex() + lm.getFrom(), area.getParagraphs().size()-1 );
                String text = area.getText( paragraph, 0, paragraph, area.getParagraphLength( paragraph ) );


                if ( paragraph != prevParagraph || text.length() != prevTextLength )
                {
                    if ( paragraph < area.getParagraphs().size()-1 )
                    {
                        int startPos = area.getAbsolutePosition( paragraph, 0 );
                        area.setStyleSpans( startPos, computeStyles.apply( text ) );
                    }
                    prevTextLength = text.length();
                    prevParagraph = paragraph;
                }
            });
        }

I see it uses lm.getFrom() but not lm.getTo() ? Maybe that's the problem ?
Or maybe it has something to do with the line: "if ( paragraph != prevParagraph || text.length() != prevTextLength )" ?
Or possibly something else ?

If you can improve the code a PR will be welcome :-)