When reviewing a page in the Page Curation Tool, reviewers are prompted to leave a message on the talk page of the page creator (or when unreviewing a page, the reviewer). The tool limits this to 250 characters, but at least from the user's point of view there's no obvious reason why it should be limited. In any case 250 characters is a very tight restriction.
There is a DB field that looks relevant, but luckily it is unused and null in production. I'll go ahead and drop that too:
mysql:wikiadmin@db1073 [enwiki]> SELECT * FROM pagetriage_log WHERE ptrl_comment IS NOT NULL; Empty set (0.02 sec)
Checked in betalabs - the limit is removed along with the character counting ( "[# of characters] left" ). Also checked Special:Log/pagetriage-curation for text excerpts displayed.
QA recommendation: Resolve.
Turns out it's just breaking when there is an = in the message because we're not specifying the text we're passing into the template as the value for the 3rd parameter. I will create a new task and submit a patch assuming this is as easy as I think it is to fix.