As show in https://jsfiddle.net/Lvau5ofp/2/, even though onchange event is fired from a user gesture, the onchange event handler cannot be used to start video elements.
<rdar://problem/69132811>
Created attachment 409118 [details] Patch
This didn't landed: https://searchfox.org/wubkat/source/Source/WebCore/html/HTMLSelectElement.cpp#738 Do we need this?
Updated test case with test video: https://jsfiddle.net/wjcf9Lyk/1/show