Parsoid is also having issues:

13:37:43 mw-dberror.log:Wed Jul 29 17:37:33 UTC 2020	068460a999b7	wikidb-parsertest_	Error 1 from ChangeTags::getTags, no such table: parsertest_change_tag SELECT  ct_tag_id AS "value"  FROM parsertest_change_tag    WHERE ct_rc_id = 12 AND ct_rev_id = 12 AND ct_log_id = '19'   localhost
13:37:43 mw-dberror.log:#0 /workspace/src/includes/libs/rdbms/database/Database.php(1654): Wikimedia\Rdbms\Database->getQueryExceptionAndLog(string, integer, string, string)
13:37:43 mw-dberror.log:#1 /workspace/src/includes/libs/rdbms/database/Database.php(1227): Wikimedia\Rdbms\Database->reportQueryError(string, integer, string, string, boolean)

see https://integration.wikimedia.org/ci/job/parsoidsvc-parsertests-docker/9758/console for example.

Seems like the temporary DB used for parser tests isn't creating the _change_tag table?

Change 617145 had a related patch set uploaded (by Krinkle; owner: Krinkle):
[mediawiki/core@REL1_34] phpunit: Acknowledge known dberror from SpecialPageFatalTest

https://gerrit.wikimedia.org/r/617145

Change 617145 merged by Krinkle:
[mediawiki/core@REL1_34] phpunit: Acknowledge known dberror from SpecialPageFatalTest

https://gerrit.wikimedia.org/r/617145

Change 617226 had a related patch set uploaded (by Krinkle; owner: Aaron Schulz):
[mediawiki/core@REL1_34] Cleanup up excess commit() call in LocalRepoTest

https://gerrit.wikimedia.org/r/617226

Change 617226 merged by Krinkle:
[mediawiki/core@REL1_34] Cleanup up excess commit() call in LocalRepoTest

https://gerrit.wikimedia.org/r/617226

@Krinkle the master branch is failing too, not just the REL1_34 branch. (At least for Parsoid CI.) Is there a separate task filed for that?

This task is about mediawiki/core where master passes but REL1_34 is failing due to a newer assertion not yet passing because of a few lastminute fixes that need backporting.

I don't know about the job you mention, please file a separate task. If that's failing on master, then it's unlikely to be related to this task and likely not to be an issue we have literally already fixed. However it might be similar to some of the other things we found in the history of T246358.

Change 617247 had a related patch set uploaded (by Krinkle; owner: Krinkle):
[integration/config@master] jjb: Skip assert-no-mediawiki-errors on REL1_31 and REL1_34

https://gerrit.wikimedia.org/r/617247

In T259123#6346388, @Krinkle wrote:

This task is about mediawiki/core where master passes but REL1_34 is failing due to a newer assertion not yet passing because of a few lastminute fixes that need backporting.

Ok, filed T259186: Parsoid CI is failing when parser tests are run.

Change 617247 merged by jenkins-bot:
[integration/config@master] jjb: Skip assert-no-mediawiki-errors on REL1_31 and REL1_34

https://gerrit.wikimedia.org/r/617247