Text highlighting for ES6 template literals (backticks) in IntelliJ IDEA
In 2019.3:
Settings > Editor > Color Scheme > General > Code > Injected language fragment
And deselect Background
I finally found the answer. I'll let this stay in case anyone else wonders.
Editor -> Colors & Fonts -> General -> Injected language fragment -> Uncheck background on the right side panel
Cheers
... and for some reason they've changed this again in 2017.2
Now go to Preferences -> Editor -> Color Scheme -> General -> Injected language fragment and uncheck "Background"