In order to use it, it's necessary to install on each client machine the Browser Print SDK.
https://www.zebra.com/us/en/products/software/barcode-printers/link-os/browser-print.html

Drag the "ZebraPrinter" web block to the page you want to use the functionality.

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You can then use the included actions to list the available printers and request printing using the Zebra ZPL format.

E.g: "'^XA ^FO90,200 ^BY2.5,2,10^BCR,200,128,Y,N,,U ^FDDFW'123456789'^FS ^XZ'"