How to actually connect to the printer?

[apperside]

Hello,
I am developing an app and I am trying to find a way to print labels directly from browser (especially mobile devices).
I found this library but browsing the code I didn't found where you tell some kind of detail about the printer. How can the library know to which printer to connect?

[alinaeemx]

@apperside
Did you find any solution for this issue (printing from a browser to a thermal printer)?