Chrome Version       : <Copy from: 'about:version'>
OS Version: 
URLs (if applicable) : data:text/html,<div></div><script>document.write(getComputedStyle(document.querySelector("div")).lineHeight)</script>
Other browsers tested:
  Add OK or FAIL after other browsers where you have tested this issue:
     Safari: PASS
    Firefox: PASS
    IE/Edge: FAIL

What steps will reproduce the problem?
1. Open the URL above.

What is the expected result?
A pixel value.

What happens instead of that?
normal is serialized.

https://drafts.csswg.org/cssom/#resolved-values includes 'line-height' in the list of properties for:

> The resolved value is the used value.