My quizzes don’t work any more. Is everything broken in WordPress 5.1?

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value="2" id="single_page" /> Show all questions on a single page.	singlepage='on' or singlepage='off'
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checked="checked" value="2" id="multiple_chances" /> Allow multiple opportunites to answer questions.*	multiplechances='on' or multiplechances='off'
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checked="checked" value="2" id="show_hints" /> Show the hints, when available.	hints='on' or hints='off'
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checked="checked" value="2" id="show_start" /> Display Quiz Start Screen before quiz.	startscreen='on' or startscreen='off'
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checked="checked" value="2" id="show_final" /> Display Quiz Final Screen after quiz.	finalscreen='on' or finalscreen='off'
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value="2" id="random_questions" /> Randomly arrange questions.	randomq='on' or randomq='off'
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value="2" id="random_answers" /> Randomly arrange answers.	randoma='on' or randoma='off'
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value="0" id="no-show" /> Never indicate the correct answers.	showanswers='never'
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value="1" id="show-end" /> Indicate the correct answers only at the end of the quiz.	showanswers='end'
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checked="checked" value="2" id="show-between" /> Indicate the correct answers at the end of each question.