in MS answers, reason of issue stays unknown. that doesnt mean its not mx. Im just reporting my experience that i discover its a mx5 bug. whatever you believe not my business.
tested it in 3 different systems.
1- installed mx -> explorer bug appeared
2- uninstalled mx + fix win -> bug gone
3- installed mx -> explorer bug appeared
4- uninstalled mx + fix win -> bug gone
if you realise that bug was happenning when i quit the game, which is fullscreen. thats how i realize, that its the same bug caused by mx5. i thought its a conflict btw the game and mx because it was the only game i play. i had that explorer bug too, but i didnt know that its caused by mx5 too.
reason why i keep trying mx5 in my systems is, nice pop up option of embedded videos in webpages. uc browser which i like is outdated, and yandex browser's popup which i use as my main is poor compared to mx5.