As discussed in https://gerrit.wikimedia.org/r/145395.
Parsoid treated {{!}} as a magic word only in table context. Jackmcbarn's patch to core ( https://gerrit.wikimedia.org/r/136234 ) makes {{!}} a magic word in *all* contexts. So Parsoid should probably do the same now... which requires some tweaks to the tokenizer.
Hence this bug.
Version: unspecified
Severity: normal