When there are more than one screen of notes I find the mouse wheel to be a bit slow and if there's a few hundred my finger gets tired. A scroll bar on the note list (and maybe on the "Note attachments" screen as well) would speed things up greatly.
I'm currently using 2.7.15 in dark mode on Win7 and Win10
I just made the Joplin upgrade from 2.7.14 to 2.7.15 on my Win10 system after reading your post. I use the dark theme as well.
But I see a scrollbar for the list of notes under both versions. The appearance of the scrollbar is the same like in the notebooks & tags list.
I see the scrollbar in the tags list. Never looked at that before. It's the same color as the background on the notes list so that's why I never saw it before. It's so narrow and the color matches so well I just assumed there was none. I still can't see it but I'll have to assume it's there and try to get the mouse cursor over it so I can scroll. I'll assume there's one as well on the note attachments list but invisible scroll bars are a challenge to us older folks.
Thanks
Yes, it‘s not easy to see. But you may change the colour scheme to have a better experience.
I fully agree with what @HarSel has to say about lack of contrast, and this issue has been discussed before: Themes too difficult - #17 by former_evernotist
Unfortunately, CSS tweaking is no easy fix and can cause issues when Joplin is updated (which fortunately happens quite often).
I also agree with HarSel's opinion that scroll bars are to small in width: In my humble opinion those narrow bars (and even those 'dynamic' ones that get wider when you use them) belong to a widespread, but annoying fashion of UX design...
In my case (and others I would guess) it's a matter of cataracts making the distinction between similar shades of anything very difficult. Dark mode is mandatory, otherwise the brightness drowns out everything.