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5
Votes

Javascript Error: Super expression must either be null or a function

Dear Syncfusion Devs,

I've recognized the following js error when playing arround with the tabs component within the latest release. It hapens on a irregulary basis of reloads. This issue cause that as example a sfbutton isn't working anymore that is on the same page. Please check the attachment.

"Uncaught TypeError: Super expression must either be null or a function"


Example Code:



<SfTab>
    <TabItems>
        <TabItem Content="Twitter is an online social networking service that enables users to send and read short 140-charactermessages called tweets.Registered users can read and post tweets, but those who are unregistered can only readthem.Users access Twitter through the website interface, SMS or mobile device app Twitter Inc. is based in SanFrancisco and has more than 25 offices around the world.Twitter was created in March 2006 by Jack Dorsey,Evan Williams, Biz Stone, and Noah Glass and launched in July 2006. The service rapidly gained worldwide popularity,with more than 100 million users posting 340 million tweets a day in 2012.The service also handled 1.6 billionsearch queries per day.">
            <ChildContent>
                <TabHeader Text="Twitter"></TabHeader>
            </ChildContent>
        </TabItem>
        <TabItem Content="Facebook is an online social networking service headquartered in Menlo Park, California. Its website waslaunched on February 4, 2004, by Mark Zuckerberg with his Harvard College roommates and fellow students EduardoSaverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes.">
            <ChildContent>
                <TabHeader Text="Facebook"></TabHeader>
            </ChildContent>
        </TabItem>
        <TabItem Content="WhatsApp Messenger is a proprietary cross-platform instant messaging client for smartphones that operatesunder a subscription business model.It uses the Internet to send text messages, images, video, user location andaudio media messages to other users using standard cellular mobile numbers. As of February 2016, WhatsApp had a userbase of up to one billion,[10] making it the most globally popular messaging application.WhatsApp Inc., based inMountain View, California, was acquired by Facebook Inc.on February 19, 2014, for approximately US$19.3 billion.">
            <ChildContent>
                <TabHeader Text="Whatsapp"></TabHeader>
            </ChildContent>
        </TabItem>
    </TabItems>
</SfTab>





Steps to reproduce:

  1. Reload multiple time thes site: 
    https://blazor.syncfusion.com/demos/tabs/default-functionalities?theme=bootstrap4
      with dev console open
    
    

  2. Watch the issue