For my Bartender label I've created a HTML to display in the Markup Language Text tool.
When I view the HTML code separately in browser it displays the bar-code correctly.

But when I preview the label it doesn't show the bar-code.
Can't I refer the red highlighted URLs through Bartender? I'm guessing that's why the bar-code doesn't appear since I used jQuery to display the bar-code.


I don't think it is possible. See the following link: http://help.seagullscientific.com/2019/en/Index.htm#Supported_HTMLTags.htm
I can see you connect the field to a database. If this database contains the data you can just create a barcode and connect the Databasefield to it.