Changing wallpaper makes the background go grey

[leolost2605]

What Happened?

When changing wallpaper from settings the background goes gray with some fading. The multitasking view shows the correct wallpaper. Logging in and out fixes the issue.
Also if you play around with it a little and change wallpaper then immediately open multitasking view funny things will happen. For example now the normal desktop background has the correct wallpaper while the multitasking view is grey and sometimes even offset...?

Steps to Reproduce

1. (Probably) compile gala from latest master
2. Open settings
3. Change wallpaper
4. Observe a grey background

Expected Behavior

Show the new wallpaper without logging in and out

OS Version

7.x (Horus)

Software Version

Compiled from git

Log Output

No response

Hardware Info

No response

[leolost2605]

bisect says it's #1819. Seems it's necessary after all :(