Hi Thijs,
You mention the use of autofill, does the issue also occur when manually entering credentials?
The apps you mention have different (sub)domain names (e.g. esri.com or arcgis.com - perhaps different from your organizational (sub)domain login). Could it be that there is a previous version password stored in autofill for these specific domains other than your usual ArcGIS Online (sub)domain?
From here I am able to successfully login to both apps you mention.
Hope this helps and all the best,
Lynn
