How to fix: Microsoft Edge grey screen, freeze or unresponsive after idle


The problem

I've had the issue for a while where a Microsoft Edge browser window freezes and becomes unresponsive after sitting idle for a while. The behaviour is strange, because the interactive elements underneath the freeze will still work and websites still load, but the browser window is not redrawn. If you switch tabs, the browser window will simply render a grey screen, as visible in the screenshot above. Microsoft Edge eventually gets itself together after a solid minute, but a repaint of the brower window can be forced by minimising, then maximising the window again. This is only a temporary fix as the behaviour returns.

Solutions which won't work

The following solutions won't work, because I have tested them:

  1. Disabling hardware acceleration in the settings
  2. Disabling tab freeze or tab sleep in edge://flags
  3. Disabling media router component in edge://flags

Solution which will work

  1. Enter edge://flags in the navigation bar
  2. Search for "Calculate window occlusion on Windows"
  3. Select "Disable" from the dropdown menu for this flag
  4. Restart Microsoft Edge

I've found the solution in a Google Chrome support thread. The problem occurs for the Google Chrome browser as well, so it is likely a problem which originates from the Chromium open source project. I haven't found any articles detailing a fix for Microsoft Edge, so this might be the first one for Edge. It is unacceptable that a bug of this caliber makes its way into stable browsers.