In Qt 4, those events were queued and sent when event loop was run without excluding those events. While it makes sense that this behaves this way as it is only meant for filtering the events, due to this behavior change, some code which relies on native input events is more difficult to port to Qt 5.
|For Gerrit Dashboard: QTBUG-69687|
|235748,2||Windows: Fix QEventLoop::ExcludeUserInputEvents for pointer events||dev||qt/qtbase||Status: MERGED||+2||0|
|235933,12||xcb: respect QEventLoop::ExcludeUserInputEvents in native event handlers||5.12||qt/qtbase||Status: MERGED||-2||0|
|237331,11||xcb: call processXcbEvents() on every event loop iteration||5.12||qt/qtbase||Status: ABANDONED||+1||0|
|239011,17||xcb: call processXcbEvents() on every event loop iteration||5.12||qt/qtbase||Status: MERGED||-2||0|
|256136,5||Cocoa: always send queued user input events||5.12||qt/qtbase||Status: MERGED||+2||0|