Configure DPI for Sommelier (X11)

• Go to chrome://os-settings/display
• Press Ctrl + Shift + J to open the debug console
• Paste the following into the debug console and press Enter:

div = document.createElement('div');
div.style = 'height: 1in; width: 1in;';
document.body.appendChild(div);

chrome.system.display.getInfo(displayUnitInfo => {
  let displayZoomFactor = displayUnitInfo[0].displayZoomFactor.toFixed(1),
              screenDPI = div.offsetWidth,
              scaledDPI = screenDPI * (window.devicePixelRatio || 1),
             defaultDPI = (scaledDPI / displayZoomFactor).toFixed(0);

  console.log(`DPI in default scale: %c${defaultDPI}`, 'color: cyan;');
});

• An DPI value should be printed now, copy the DPI value
• Close the settings page and the console
• Paste the following to terminal and press Enter: (replace [DPI_value] with the DPI value you just copied)

echo '[DPI_value]' > ${CREW_PREFIX:-/usr/local}/etc/sommelier.dpi
restartsommelier

• Now the DPI should be configured correctly, you can verify it by starting an X11 application and checking the font size.