Folder icon color not updating with the rest of the theme

I tried changing elements of the Nextcloud interface under Admin>Theming, but the color of the folder icons isn’t updating. The top bar and checkboxes switch to the new color immediately, but the folder icons are still blue. Changes to the logo, login image and slogan were also applied immediately. The page in the Admin manual on theming says:

Color: The color of header bar, checkboxes and folder icon

I tried restarting the server, clearing my browser cache and logging in from other computers. I know this isn’t a mission-critical issue, but I would appreciate it if anyone could tell me what’s going on. Let me know if there’s any more information I can provide.

This is currently being worked on: