First, there is a solution, read on... I am running a Surfacebook 3000x2000 resolution with an external 4K monitor 4096x2160 resolution. When I open calc every third horizontal cell separation line is missing from the display. At first I thought this might be a feature, but later realized it's a bug. The "solution" is to set Windows LibreOffice application properties to "Override high DPI scaling behavior" "Scaling performed by: System". With this property set all calc row lines reappear. This new Windows 10 "feature" is messing up many more mature Windows products on high DPI displays. I'm finding many applications have a file like "scalc.exe.manifest" which contain XML like: <asmv3:application> <asmv3:windowsSettings xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings"> <dpiAware>false</dpiAware> </asmv3:windowsSettings> </asmv3:application> The critical part is "<dpiAware>false</dpiAware>" to allow an application to display as it has on prior MS Windows products. I adjusted this setting on the LibreOffice launcher and now everything looks as it has on earlier versions, and matches appearance under Linux.
Thank you for reporting the bug. it seems you're using an old version of LibreOffice. Could you please try to reproduce it with the latest version of LibreOffice from https://www.libreoffice.org/download/libreoffice-fresh/ ? I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the latest version.
Created attachment 136672 [details] 4K Screen-Application capture showing missing lines "Compatibility" settings turned off so application can run natively on 4K screen, Surface book Pro i7 external display port 43" monitor, screen scaling 1:1
LibreOffice in general has several problems on high DPI screens ranging in severity from minor nuisance (Calc missing lines) to crippling (Impress presentation mode). These display issues may require a fairly senior software developer to overhaul the LibreOffice display architecture framework. i.e. in my opinion this isn't a "simple software fix".
Seems like the relevant element is dpiAwareness for Win10 version 1607 or later: https://msdn.microsoft.com/en-us/library/windows/desktop/aa374191(v=vs.85).aspx Can you check if permonitor or permonitorv2 works, or only unaware does?
How would I check permonitor, permonitorv2, or unaware? Here is what I did; I set the LibreOffice5.4.2.2 x64 desktop shortcut "Compatibility" to "Override high DPI scaling behavior" to "Scaling performed by" [Application], [System], [System (Enhanced)]. All three modes seem to work with SCalc. Turn off "Override high DPI scaling behavior" and the problem of missing or extremely light horizontal cell lines reappear. Either of the "System" compatibility modes is desirable. The "Application" setting makes the application look like it's been zoomed to 2x... large and gross.
BTW, the adapter I use for the HDMI 4K output is the Microsoft recommended/supported "Cable Matters DP 1.2". The Surfacebook 4K screen [3000x2000 @150%] shows lines as I expect to see them. It's the external display, 43" 4K [4096 x 2160 @100%] monitor driven through the Cable Matters DP 1.2 which is experiencing the Lost Lines and/or missing icons issue. Overriding the DPI behavior makes the problem disappear.
Setting the 4096 x 2160 external monitor to 150% makes the lines reappear.
(In reply to craig@arno.com from comment #5) > How would I check permonitor, permonitorv2, or unaware? Oh, I don't know how the manifests works, based on the description I thought you managed to set that somehow. Either way, thanks for the details!
Does it happen with LibreOffice 6.0 RC3 from https://wiki.documentfoundation.org/QA/GetInvolved#Test_Pre-releases ? I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the latest version.
Missing lines still persist in 6.0.0.3: Version: 6.0.0.3 (x64) Build ID: 64a0f66915f38c6217de274f0aa8e15618924765 CPU threads: 4; OS: Windows 10.0; UI render: default; Locale: en-US (en_US); Calc: group
Hello Craig, A new major release of LibreOffice is available since this bug was reported. Could you please try to reproduce it with the latest version of LibreOffice from https://www.libreoffice.org/download/libreoffice-fresh/ ? I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the latest version.
Version checked 6.1.3.2 (x64) Missing lines problem resolved. Checked scaling at 100%, 125%, 150%, 175%, 200%, 225%, 250%, 300%, 350% on the 43" 4K [4096 x 2160 @59Hz] monitor. Also performed a quicker test on the primary Surfacebook 3000x2000 display. Looks like you nailed it for Calc! This bug is resolved on my hardware. ======== I checked Impress "Bug 106526 - Impress dual head presentation to 4K or QHD resolution monitor or projector has presentation screen tearing" and that bug still exists.
Thank you Craig for extensive testing. This is WorksForMe than, but let's mark as a duplicate of Bug 119020. *** This bug has been marked as a duplicate of bug 119020 ***