Test only in one device of your choice. In a Moodle site, Install a quiz accessrule not supported by the app. Enter the quiz and check message: This quiz can't be attempted in the app because it has access rules not supported by the app is shown with the list of rules. Add a remote css url that hides the whole message: .addon-mod_quiz-unsupported-rules { display: none; } Test again and check message is not shown. Change the css to hide only the rules (only one letter change): .addon-mod_quiz-unsupported-rule { display: none; } Test again and check message is shown but the list of unsupported rules not. You can also hide one rule using: .addon-mod_quiz-unsupported-rule-RULENAME class.