I have an app for the Mac where I use WebView (not WKWebView) and many of the other classes of the WebView set (like the DOM classes) to process the web site etc. Loading web sites does work great from the beginning of the MacOSX until and including macOS 10.11. But under macOSX 10.12 there are issues: on some sites (like vimeo.com) the videos do no longer load, on others (like youtube) there's no problem at all. The web sites where it does not work do only give a generic error like "Oops, the video can not be played".
This problem seems to be related to the macOS "Base SDK" which was used to build the App. An older version of my App (build with an older SDK) does still play all the videos. Only the App that was built with the SDK for 10.12 shows this issue, and only under macOS 10.12, not under macOS 10.11.
Are there any new requirements for WebView which might prevent that the videos do play? Unfortunately the current XCode doeno longer support older SDKs, so I'm unable to build the App with an older SDK (I do not need any new features of 10.12, so using an olde SDK would not be an issue).
Any ideas what could go wrong?
Would it be possible to install older SDKs and use these instead of the new ones?
