When importing an Alembic Mesh clicking on any of its modifiers will create a property drop-down with the name >>>@!&*#<<< (screenshot attached). Every time a modifier is clicked it adds a new drop-down and the drop-downs are persistent until Max is restarted.
This issue happens in the builds in this repository an a self compiled build(commit 20d5e00a) with Visual Studio 2019 CE.