What I know: I happened when you load file. Most of the cases was related to the PHP highlighter and FTP, often when standalone close bracket was in file.
I made some fixes in hihglighters, I made some fixes in IDE to prevent flickering e.t.c. -- <https://forum.pspad.com/read.php?6,78195,78204> PSPad freeware editor https://www.pspad.com
