I found a post saying this was resolved in 2016. Not so. I have the same problem in 2017 and 2019. Custom buttons appear as expected when first launching the panel but do NOT reposition when panel is resized.
by: Leon G. | over a year ago | General Enhancements
Comments
In Customizer, on the Options tab of the button control, there is an "Anchored" drop box. You can select Top/left, Top/Right, etc.