Hello list, Another difference, perhaps the result of my lack of knowledge, but a difference. The following example produces different results for the fourth sequence, with the index being passed one item under MkIV and two items under LMTX. (The code is stripped out of a much more complex bit to show the issue.) % macros=mkvi \starttexdefinition unexpanded startBlockQuotation     \dosingleempty\dostartBlockQuotation \stoptexdefinition \starttexdefinition dostartBlockQuotation [#SETUPS]     \getrawparameters[BlockQuotation]       [index=,#SETUPS]     \expandafter\processcommalist       \expandafter[\BlockQuotationindex]\doIndexIt{} \stoptexdefinition \starttexdefinition stopBlockQuotation \stoptexdefinition \starttexdefinition doIndexIt #INDEXTERM   indexer sees #INDEXTERM\   \index{#INDEXTERM} \stoptexdefinition \starttext \startBlockQuotation[index=aaa]  \startparagraph   1 \quad when indexing aaa.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={aab}]  \startparagraph   2 \quad when indexing \{aab\}.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={aac, aad}]  \startparagraph   3 \quad when indexing \{aac, aad\}.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={{aae, aaf}}]  \startparagraph   4 \quad when indexing \{\{aae, aaf\}\}.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={{{aag, aah}}}]  \startparagraph   5 \quad when indexing \{\{\{aag, aah\}\}\}.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={{aai, aaj},{aak, aal}}]  \startparagraph   6 \quad when indexing \{\{aai, aaj\},\{aak, aal\}\}.  \stopparagraph \stopBlockQuotation \startBlockQuotation[index={{{aam, aan}},{{aao, aap}}}]  \startparagraph   7 \quad when indexing \{\{\{aam, aan\}\},\{\{aao, aap\}\}\}.  \stopparagraph \stopBlockQuotation \placeindex \stoptext Did I misuse the comma list processing, or is this a bug? -- Rik