Investigate "delete character" background color erase.

VTE seems to recolor a lot more cells with the current background color than xterm.

Run echo -ne "\033[44mab\033[43m\033[2D\033[P\033[m\n"

expected (xterm): the right-most cell is colored in yellow as that cell is newly "scrolled in"/created.

actual result(vte): The whole line except the very first cell is colored in yellow.

Version: vte 0.56.3