if I open a text file with thousands of lines, text area becomes black when clicked or scrolled after a while
gedit 3.34 on Arch Linux
download the attached valgrind log
open it with gedit
after the file to be completelly loaded by gedit, wait 1.5 minute or more
click on any word or scroll the text
Result: the line of the clicked word becomes black. The text area becomes black after scrolling.
Watch the attached screen recording please.