Issues with IntelliJ on a 4K screen

Question

I splurged and bought one of those high definition 4K screens. More specifically, the Dell UltraSharp 4k UP3216Q 31.5", combined with a new PC running Windows 10.

When the computer occasionally reboots, it goes into a mode where when I load IntelliJ, it shows the following error message:

8:16 PM You may need to manually configure the HiDPI mode to prevent UI scaling issues. See the troubleshooting guide.

The interesting thing is that when it's running in this mode, I actually like the way IntelliJ looks. I like it because it's running in true sharp 4K mode, and at the same time, all the fonts are large enough to be legible, and not require a magnetic resonance microscope or a monocle to make out the letters.

However, other times, when the system boots up, I do not get that error, meaning everything is functioning normally, but in that case, all the fonts are so tiny as to be illegible. It literally hurts my eyes to look at it, and the only alternatives I have left at that point is to either drop down from 3840x2160 into 1920x1080, or to go into the settings, and start increasing the font sizes, which is annoying. Not to mention that if I drop down into 1920x1080 mode, then the quality of what I am looking at degrades, everything starts looking pixelated...

Is there anything that can be done to stabilize the situation on these new 4K screens so that IntelliJ looks normal?

Answer 1

Try this:

Help > Edit Custom VM Options:

-Dsun.java2d.uiScale.enabled=true

More information can be found here: https://intellij-support.jetbrains.com/hc/en-us/articles/115001260010-Troubleshooting-IDE-scaling-DPI-issues-on-Windows

If that does not help create a ticket in the JetBrains issue tracker: https://youtrack.jetbrains.com/ They are usually very responsive.

Answer 2

Another possibility is that you have the Windows UI scaling value for the screen set to a non-integral value in display settings. This messed me up, I had the setting to 175%, while the default is 200%. Intellij (and many other applications) will not scale properly if that is set to a non-integral scaling value.

As soon as I switch this back to 200% Intellij scales perfectly.