cf.
https://gerrit.wikimedia.org/r/#/c/267879/
13:33:37 1) ResourcesTest::testMissingDependencies
13:33:37 The module 'ext.visualEditor.mwcore' required by 'ext.math.visualEditor' must exist
13:33:37 Failed asserting that an array contains 'ext.visualEditor.mwcore'.
13:33:37
13:33:37 /mnt/jenkins-workspace/workspace/mwext-testextension-php55/src/tests/phpunit/structure/ResourcesTest.php:84
13:33:37 /mnt/jenkins-workspace/workspace/mwext-testextension-php55/src/tests/phpunit/MediaWikiTestCase.php:137
13:33:37
13:33:37 2) MathCoverageTest::testCoverage with data set #424 ('\\Coppa\\coppa\\varcoppa', '<img class="mwe-math-fallback-image-inline tex" alt="\\Coppa\\coppa\\varcoppa" src="8308ee5003aa36112414cad8ef874f85.png" />')
13:33:37 Failed to render \Coppa\coppa\varcoppa
13:33:37 Failed asserting that two strings are equal.
13:33:37 --- Expected
13:33:37 +++ Actual
13:33:37 @@ @@
13:33:37 -'<img class="mwe-math-fallback-image-inline tex" alt="\Coppa\coppa\varcoppa" src="8308ee5003aa36112414cad8ef874f85.png" />'
13:33:37 +'<strong class='error texerror'>Failed to parse (PNG conversion failed; check for correct installation of latex and dvipng (or dvips + gs + convert)): \Coppa\coppa\varcoppa</strong>
13:33:37 +'i.e. the second problem indicates that some latex greek packages are missing.
While this is yet another reason to finally disable the png rendering, we should fix the tests for now.