Hello @wordpressorgcat,
Sincere apologies for the extremely long wait, we have been a bit shorthanded and on the other hand overwhelmed with work during this covid situation.
If I understood your question correctly, you are trying to disable arrows that indicate a specific menu item has subitems? If yes, in that case you don’t need any codes.
Please go to Appearance > Customize > Header > Menu, and uncheck Top Level and/or Second+ Level Dropdown Icons.
If this is not the answer you were looking for, then please provide us with more details as well as the URL to your website and/or screenshots.
Thank you
