The plugin background is currently set to transparent. body.plugin { background: transparent; } This causes an issue when using the dark theme because the text is black and transparent background lets the dark background hide the text. I'm not sure what else this would effect, but simply commenting out that style will fix the issue as it will fallback to the default background of #fff (white). see my Facebook media post as an example - https://thephins.com/threads/nsfw-explains-o-line-performance-lack-of.91992