When opening the settings screen, the "dialog opacity" setting never gets loaded to the default value, even if different value is effectively taking place.
The default value is 60% and I can verify different values having effect but unless they're input each time the option screen gets opened, it gets reset.
It's a programming bug where a setting isn't read into a slider.
I reported it on the Codex but it's more likely you peruse this forum.
(Jesus H. Christ the captchas reallly make my eyes bleed)
