Understood. At least you know for next time 
Mind you - there will probable not be a Windows 11 so we should be good for the foreseeable future.
That said - I am finding obscure oddities even with Windows 10 being updated (in place) to a new āfeatureā version several times - like say v1607->v1709->v1809
I rebuilt a machine here that had this cadence and it ran markedly better after I stripped away the twice āupgradeā OS and and installed a clean version of Win 10 v1809.
Given the limitless computer permutations in the real world - it would be impossible for Microsoft to properly test every app, plugin etc to see what impacts are exposed when taking a machine that originally had Win 10 v1607 on it and then was subjected to several feature upgrades to arrive at v1809 some 2.5 years later.
It does not surprise me in the least that some apps simply cannot survive that many internal changes to continue operating correctly upgrade after upgrade.
VP