After the latest deploy the test wiki main page behaves unexpectedly.
Upon attempting to highlight the first utterance a IndexSizeError. This means highlighting fails which in turn means Wikispeech/this.playOrStop is not triggered and thus the play button does not change to a stop button.
On the main page this might be related to T159545: Unicode characters increase length of highlighting but it is unlikely to be the reason for the similar behavior in the second sentence of Blonde_on_Blonde.