I've seen a lot of discussion on this but they all seem to apply to older versions of FMP. I've installed the IDAutomation_FileMakerFontEncoderFunctions, but I have no idea how to use it to generate the data matrix barcode.
That won't generate data matrix barcodes.
jbante has expressed interest in adding data matrix to Barcode Creator, but I don't know if it will actually happen. Chances are probably good with FileMaker adding support for them in Go in future releases.
You could contact TEC-IT about commercial use of their barcode generator (assuming your use is commercial, otherwise you could probably use it as-is). Assuming commercial use isn't much different from their normal generator, it would just be using Insert From URL with the target set to a container field and the URL set to "https://barcode.tec-it.com/barcode.ashx?data=" & $data & "&code=DataMatrix&dpi=96&dataseparator=". This would of course require an internet connection.
the MBS plugin can create DataMatrix barcodes
Ah, so it will.
Monkeybread Software - MBS FileMaker Plugin: Barcode.Generate
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