3D FlipBook - Dear Sir! I need your help, because this plugin, which is great by the way doesn’t show the bar when the window is scaled

Dear Sir!

I need your help, because this plugin, which is great by the way doesn’t show the bar when the window is scaled up for a long length.

https://www.steinkogler.eu/katalog2020/

<p>I need to have the bar always visible on the page.</p>