Input GPS coordinates into firebase instead of using "placepicker"

I have tried to use the place picker and works fine with address input and shows it directly in the map.

However you can't input GPS coordinates like: (45.941251032588674, 6.885589661382981) into the place picker - which i what I need.

I tried to input in a simple text field and grab the Lat lng from there, but the "document update with data type latlng will only take input from the place picker widget.

I tried to write a custom function that converts GPS coordinates from a text field into a latlng but was unsuccessful.

Any suggestion on how I might solve this?