When clicking on an object EndInputTouch sometimes fires on the press instead of the release. This was not an issue in 4.19.2 (CL-4033788) and is a regression. However the functionality doesn't appear to work at all in Main 4.21 (CL-4370874)
This was tested and reproduced in 4.20.2 (CL-4302132).
Results: EndInputTouch fires when object is pressed and released.
Expected: EndinputTouch event will activate only when mouse button is released on the object.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-64214 in the post.