rejected on Appstore now. July 3th 2019.
Message:
We identified one or more issues with a recent delivery for your app, "appname. Please correct the following issues, then upload again. ITMS-90338: Non-public API usage - The app references non-public selectors in Sonnenbraeu: _setAlwaysRunsAtForegroundPriority:. If method names in your source code match the private Apple APIs listed above, altering your method names will help prevent this app from being flagged in future submissions. In addition, note that one or more of the above ...
I removed the complete line of _setAlwaysRunsAtForegroundPriority:
as described above from code. Also the references to it. And yes, the app got released. BUT I don't know exactly the consequence of removing the property which sets the browser to foreground priority mode. I don't think its a good solution, its just a provisoric workaround to get released.