I found a really old bug in Construct 2, that prevents the user from changing the Layer background color when pasting a colorcode in the property field. Did this never got fixed?
fldr reported this bug back in early 2014 but the report got closed without comment: Link
Ashley please look into it.
Steps to Reproduce Bug
The color in the property field changes and you can even edit the color, but the background color doesn't change. When you switch the focus to everything ales and then back to the property field, the color gets reset.
The background color should change without problems.
Operating System and Service Pack
Windows 10 latest update
Construct 2 Version ID
Latest beta build (246)
Develop games in your browser. Powerful, performant & highly capable.
I think this was originally closed because the pasting is handled by the UI library, which we don't control and can't fix. So it's basically stuck as it is in C2.
It should work in C3 though, so please go ahead and file a bug if there's any similar issue there.