I'd fork and fix myself but I don't know shit about SCSS or how the theme is structured.
Old class: .chat-2ZfjoI
New class: .chat-9g_3Xj
Before and after adding fix snippet:
Fix snippet for those who want it:
#app-mount .chat-9g_3Xj {
background: rgb(0, 0, 0, var(--middle-brightness));
}