Invisible scrollbar handles in some terminal emulators

When setting theme to elementary, sakura and xfce4-terminal get scrollbars with invisible handles.
Though i use xfce4, honestly, pantheon-terminal doesnt't look too heavy to use in another DE (and i would even be happy with it).
At least with adwaita-class themes it doesn't appear (i use minwaita for now). But would be great to solve this issue too.

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