serial connection occurs messy code

serial connection occurs messy code sometimes, and always it looks very well at beginning, but messy code output suddenly。
after closing the serial connection tab, and open new one, everything goes well. Messy code as follows:

Start by reproducing the serial connection in WindTerm and observe when the output becomes messy after the connection initially looks correct. Compare the display before and after closing the serial connection tab and opening a new one, using the attached screenshot as the symptom reference. Done means serial output remains readable without reopening the tab.

Written by the indexing model from the issue text.