I am not sure this is still within the same context, but here a quote from the Venerable Dhammanando over from Dhammawheel:
The writer you quote seems to be treating the Dhammapada Commentary’s interpretation (which he approves of) as if it were the sole and normative definition of dhammā in this context. But in fact it’s unique and exceptional. Everywhere else the commentaries support the view that the writer rejects, the usual gloss being:
‘Sabbe saṅkhārā aniccā’ ti sabbe tebhūmakasaṅkhārā aniccā.
‘Sabbe dhammā anattā’ ti sabbe catubhūmakadhammā anattā.‘All saṅkhāras are impermanent’ means that all saṅkhāras belonging to the three planes are impermanent.
‘All dhammas are not self’ means that all dhammas belonging to the four planes are not self.
(SA.ii.318; )
The three planes are those of sense-desires, refined-form and formlessness. The four planes are the same with the addition of the supramundane. (Source: https://dhammawheel.com/viewtopic.php?t=16264#p232064)