Created attachment 2228 [details] screenshot The bounce bar in folder and message lists is black on blue which effectively means it is illegible. Elsewhere in claws UI bounce-bars are white on blue - there does not appear to an option for this in preferences - or in clawsker - not a option in GTK tweaking either that I can find This is only since an update to 4.0.0, which forced a reinstall of plugins, themes, etc and presumably other settings
This is a theme issue. Both the grey foreground (text) colour and the highlight colour are controlled by your theme.
I have the same issue. The colours don’t match my theme at all. In addition, for me the positions of the left-most scrollbar and the message view are the same after each start. This means I have to adjust the size every time so I can see the total number of messages in a folder, and to see the mail content. Not sure if it’s the same issue, but it happened together for me, with the update to 4.0.0. I have this issue on another system as well. (adding a second screenshot)
Created attachment 2231 [details] screenshot mgr shows claws-mail with colours not matching the theme displayed in lxappearance, plus neofetch confirming that the theme is actually active