After updating to 4.0.28 suddenly the UI elements of Zotero standalone are huge and some are fuzzy (see here http://i.imgur.com/DB9oK1M.png). Ubuntu 14.04. What could be the problem?
I can only test this in a VM, which makes things a little weird, but I'm not able to reproduce this in Ubuntu 15.04 on either a regular or HiDPI display. It's possible there's an issue with the Mozilla framework and pixel scaling on older Ubuntu versions.
Go to the Advanced pane of the Zotero preferences, open about:config at the bottom, and search for devPixels. What's the value of layout.css.devPixelsPerPx? It should be -1.0 by default. What happens if you change it to 1 or 2?
I do not have a HiDPI display (laptop is Thinkpad T440 with display resolution of 1600x900). I do not have also scale for menu and title bars enabled (in display settings). Running Firefox 44.0, Unity user interface.
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I can only test this in a VM, which makes things a little weird, but I'm not able to reproduce this in Ubuntu 15.04 on either a regular or HiDPI display. It's possible there's an issue with the Mozilla framework and pixel scaling on older Ubuntu versions.
Go to the Advanced pane of the Zotero preferences, open about:config at the bottom, and search for devPixels. What's the value of layout.css.devPixelsPerPx? It should be -1.0 by default. What happens if you change it to 1 or 2?