Regression - Several Installers do not respond to accelerators or some mouse commands

reactos-bootcd-0.4.15-dev-7961-gdcf9eb0-x86-gcc-lin-dbg

reactos-bootcd-0.4.15-dev-7749-gacb01cf-x86-gcc-lin-dbg
reactos-bootcd-0.4.15-dev-7750-gc17a654-x86-gcc-lin-dbg
REGRESSION confirmed.
Guilty commit : https://github.com/reactos/reactos/commit/c17a6542ac329160ce627267babc8c7ec67b1e86 from DougLyons in https://github.com/reactos/reactos/pull/6427 using a patch from I_Kill_Bugs in the attempt to fix CORE-14436 and CORE-16985

Affects several installers 

• Skype 6 : Similar to CORE-19487 but here with Mouse & Accelerators (while CORE-19487 was mouse message only)
• FullUpdate installer from : https://fullupdate.en.uptodown.com/windows/download Found while testing CORE-13658 using
• Kerish Doctor 2018 installer from CORE-14895
• GnuCash installer from RAPPS
• AOMEI Partition Assistant ( https://www.filepuma.com/download/aomei_partition_assistant_standard_edition_7.5.1-20639/ ) from CORE-18708

• Unable to mouve window with mouse by dragging title bar
• ESC from keyboard does NOT trigger "Cancel"

• Unable to toggle using ALT+A and ALT+D

• Clicking on "Minimize" or "Close" button have no effect