How to remove the prefix category header from the dropdown selection cleanly

[beerForo]

Issue: When I add prefixes from multiple categories, the drop-down shows all the headers in the list. But I want those headers for admin organization purposes only and I'd like the list to be seamless and not show a line or gap when they are removed. How would I do this with CSS?

Example...

Before:

----------------
TECHNOLOGY
---------------
computers
software
---------------
ENTERTAINMENT
---------------
movies
tv

After:

computers
software
movies
tv



Thanks!
How to remove the prefix category header from the dropdown selection cleanly

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