Sandboxed program (Rainmeter) can't set z-position?

[e-t-l]

Rainmeter is a "desktop skin" customization program that can set itself as always-on-the-desktop so that it is unaffected by e.g. Win+D commands that minimize all windows (I believe the relevant C++ is SetWindowPos(hwndTT, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE);).

When Rainmeter is sandboxed in a standard yellow sandbox, this window z-position is ignored, and Rainmeter's desktop skins can get minimized.

Is this something that can be fixed through the sbie config, or is it a bug?

[offhub]

Try this:

OpenWinClass=Rainmeter.exe,*

[e-t-l]

This works, although doesn't OpenWinClass=* open up all outside processes to the sandboxed one, thereby reducing security/privacy?
As a mitigation, I also added

HideNonSystemProcesses=y
HideOtherBoxes=y
Template=BlockAccessWMI

Is that reasonable?