bug: unwanted yellow background if hide all plugins

[AnsonH]

Hi there, I discovered there's a visual bug where if $show_powerline is on (which is true by default) and I've disabled all plugins, there's an unwanted yellow background at the right side of the Terminal:

set -g @plugin 'maxpetretta/tmux-monokai-pro'
set -g @monokai-plugins " "

Is it possible to remove the yellow background? Thanks a lot 🙇