From https://prv-tests.wmcloud.org/diff/brwiki/Degemer
λ (master) echo " {{1x|*test}}" | php bin/parse.php --integrated
<pre data-parsoid='{"dsr":[0,13,1,0]}'><listitem about="#mwt1" typeof="mw:Transclusion" data-parsoid='{"a":{"bullets":null},"sa":{"bullets":"*"},"autoInsertedEnd":true,"pi":[[{"k":"1"}]],"dsr":[1,13,null,null]}' data-mw='{"parts":[{"template":{"target":{"wt":"1x","href":"./Template:1x"},"params":{"1":{"wt":"*test"}},"i":0}}]}'>test</listitem></pre>The listItem token ends up in a IndentPreTk which the ListHandler ignores. The Sanitizer leaves the tag be because it isn't an html literal.