Highlighting text in multiline text box only highlights second line

I have a simple textbox that has multiline text. If I try to highlight all of the text, it only highlights the second line.

The code I am using:

assume shape 0 is a textbox object
const textbox=xs.sheet.data.shapes[0];     
 xs.sheet.addHighlightTextBox(textbox.id, 0, textbox.text.length);

image.png (8.7 KB)

Text Box Excel.zip (7.7 KB)

It seems the text start with ā€˜\nā€™ which causes the bug. We can reproduce this issue.
We have opened the following new ticket(s) in our internal issue tracking system and will deliver their fixes according to the terms mentioned in Free Support Policies.

Issue ID(s): CELLSGRIDJS-757

one more ,
when use this code
xs.sheet.addHighlightTextBox(textbox.id, 1, textbox.text.length);
it cannot cover the last charactor of the text .here the last dot is not covered.
so we raise another issue :

Issue ID(s): CELLSGRIDJS-758

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