Apple has updated its new HomePod mini with support for 18W power adapters. Previously, the HomePod mini required a 20W power adapter, but with a Software Update 14.3 this has now changed.
Apple includes a 20W USB-C wall adapter in the box with HomePod mini, but when I first tested a 18W charger for the HomePod mini review. Using a 18W charger caused the HomePod mini to display an orange circle on the display. However, with the latest firmware 14.3, you can now use it for your HomePod mini. Then take the 20W adapter that came with the HomePod mini for your iPhone giving you better charging performance.