When the wikitext contains an HTML table that includes </tr> tags but no corresponding <tr> tags, the table renders fine in viewing mode and in VE.
Renders as intended.
However, when any edit to the table is made, Parsoid (presumably) strips the < from all the </tr> tags.
Reported dif: https://en.wikipedia.org/w/index.php?title=2005%E2%80%9306_Polish_Basketball_League&diff=570501618&oldid=569248952
This isn't something that Parsoid can expect to encounter frequently, but it shouldn't make a mess of it when it does.