无法使用功能区按钮打开对话框

Question

我们有一个Outlook网络插件，其清单中定义了功能区按钮。

                            <Control xsi:type="Button" id="msgComposeSettingsButton">
                                <Label resid="funcComposeButtonLabel2" />
                                <Supertip>
                                    <Title resid="funcComposeSuperTipTitle2" />
                                    <Description resid="funcComposeSuperTipDescription2" />
                                </Supertip>
                                <Icon>
                                    <bt:Image size="16" resid="settings-16" />
                                    <bt:Image size="32" resid="settings-32" />
                                    <bt:Image size="80" resid="settings-80" />
                                </Icon>
                                <Action xsi:type="ExecuteFunction">
                                    <FunctionName>loadSettings</FunctionName>
                                </Action>
                            </Control>

loadSettings函数在函数文件中定义，该文件也在清单中定义。 loadSettings函数从Office Api调用displayDialogAsync方法。

Office.context.ui.displayDialogAsync(
    options.url,
    options.dialogOptions,
    function (asyncResult) {
        if (asyncResult.status === Office.AsyncResultStatus.Failed) {
            let errorMessage = null;

            log('ERROR', asyncResult.error);

            // In addition to general system errors, there are 3 specific errors for
            // displayDialogAsync that you can handle individually.
            switch (asyncResult.error.code) {
            case 12004:
                errorMessage = 'Domain is not trusted';
                break;
            case 12005:
                errorMessage = 'HTTPS is required';
                break;
            case 12007:
                errorMessage = 'A dialog is already opened.';
                break;
            default:
                errorMessage = asyncResult.error.message;
                break;
            }

            log('ERROR', errorMessage);
        }
        else {
            _dialog = asyncResult.value;
            _dialog.addEventHandler(Office.EventType.DialogMessageReceived, handleDialogMessageEvent);
            _dialog.addEventHandler(Office.EventType.DialogEventReceived, eventReceivedHandler);
        }
    }
);

该对话框在每个经过测试的平台（Outlook for Windows和OWA（IE，Firefox，Chrome））中呈现并打开，除了Outlook for Mac上的少数几个。为什么对话框在Outlook for Mac上大多数情况下都能正常工作，但对于少数人来说却没有？