I don't know what this refers to I found the following resources that may be useful: https://docs.joomla.org/J4.x:Web_Assets, and for reference, this older post discussing the same error message: viewtopic.php?t=990772 may be of some use.
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<jdoc:include type="styles" />Statistics: Posted by AMurray — Sun Apr 07, 2024 10:01 pm