Drag, alt, and resizing are all working incorrectly & create new non-existent objects
Items I select and resize seem to adjust from arbitrary points that appear, unrelated to the shape of the geometry. Attached, is a screenshot where I changed the scale of the blue diamond. The other green selected box doesn't actually exist, but is now included in the geometry of the original. If you group an object which has one of these phantoms, it will stay in the group indefinitely. Additionally, the alt-drag feature creates many duplicates. If you're scaling using the alt-command, it will work for a second and then start duplicating.
I am on Illustrator 22.1,
Mac OSX High Sierra, 10.13.4 (17E199)
Please accept my sincere apology for the inconvenience. Please get in touch with us at any of the other support channels – https://helpx.adobe.com/support.html . Since this is not a generic issue that we can reproduce at our end, we will need someone to look into your machine to figure out what is going on here.
Thanks & Regards,