I think it's about having alternating colors in the tree views (collections list and items list). They're present on macOS (and maybe Linux), but not on Windows. We're just following Windows conventions, though. Microsoft doesn't use them in Explorer (at least on Windows 7 for me), and Mozilla doesn't use them in Firefox (e.g., in the bookmark/history browser), which is why they don't appear in our tree views by default, since we haven't actually configured this differently. I'm not sure if this is any different on Windows 10.
We could enable them in Standalone on Windows — they seem like a UI improvement to me — but we'd have to make a decision to go against the OS conventions.
For awhile, I hacked the Zotero .jar file to enable them, but it got to be too much work. iTunes on Windows also uses the bi-color tree, so enabling it wouldn't be unheard of.
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We could enable them in Standalone on Windows — they seem like a UI improvement to me — but we'd have to make a decision to go against the OS conventions.
I was also looking for this feature, as Mendeley interface is much more scanable (wider rows, alternate colours).
Could you please let me know what tweaks you made to achieve this?
I'm fairly proficient in CSS but got stuck once I got into the .jar file.
Thank you for your help!