Created attachment 232184 [details] Screenshot: an almost invisible scroll bar, adjacent to a normal scroll bar <https://docs.freebsd.org/en/books/handbook/book/> for example. For a few minutes, I was convinced that the scroll bar was entirely missing. Eventually, I realised that the bar is present but nearly invisible. The bar is (debatably) far too narrow, far too faint (lacking contrast). Unnecessarily difficult to discover with a pointing device. IMHO this is especially troublesome where the faint miniscule bar is adjacent to a traditional, accessible scroll bar (screenshot attached).
At <https://docs.freebsd.org/mn/books/handbook/book/> the scroll bar for the table of contents: * appears whilst the page loads * disappears completely :-(
(In reply to Graham Perrin from comment #1) On closer inspection, that is a symptom of bug 262818 when the (incomplete translated) Handbook loads in e.g. Falkon with a window at a particular size.