[Interest] Fallback (hicolor) theme in resource (.qrc) on Mac not working

[Elvis Stansvik]

On Mac and Windows, I'm bundling parts of the Breeze icon theme in the
application resources.

E.g. I have resources like

:/icons/breeze/actions/24/document-open.svg
:/icons/breeze/actions/24/help-about.svg
:/icons/breeze/actions/24/document-close.svg
...
:/icons/breeze/index.theme

and I'm calling QIcon::setThemeName("breeze") on Windows/Mac. This was
working fine.

I kept application specific icons directly in :/icons. For example:

:/icons/myapp-some-action.svg
:/icons/myapp-some-other-action.svg
...

Recently though, I went ahead and moved my application-specific icons
into the hicolor theme, e.g:

:/icons/hicolor/myapp-some-action.svg
:/icons/hicolor/myapp-some-other-action.svg
...
:/icons/hicolor/index.theme

And started referring to them by their theme name instead. E.g.
"myapp-some-action" instead of using the QRC file paths.

I expected this would work, since hicolor is the fallback theme
(according to Freedesktop Icon Specification).

It works on Linux. It's not working on Mac though :/ The embedded
Breeze icon theme works fine, but it seems it's not falling back to my
embedded hicolor theme, so my application specific icons are not
shown. I haven't tested on Windows yet.

Anyone using a setup like this on Windows/Mac? Where you bundle both

 1. some general theme (e.g. Breeze), and
 2. a hicolor fallback theme with your application icons

both inside the application resources (.qrc).

Thanks in advance for any help.

Elvis