Weird issue with window background color

[dma]

Electrum when launched by Oz does not have the right window background color.

To reproduce:

Start electrum the normal way.

Interestingly:

oz launch -n electrum [wait a few seconds] electrum ^ launched by oz while sandbox already setup

Results in electrum having the right window background color. It's as though electrum starts too quickly and some part of the sandbox filesystem isn't ready..