[Gelöst] WPML is crushing functionality of other plugin

Background of the issue:
I am trying to use WPML with the Real3D Flipbook & PDF Viewer plugin. When WPML is activated, all PDF Viewer functionality stops working on the frontend, and I get some errors in the console. I tried using an older version of WPML, but it didn't help. I switched plugins on and off one by one, and when I deactivate WPML Multilingual CMS, the PDF viewer starts working correctly. This issue didn't occur some time ago. Link to a page where the issue can be seen: versteckter Link

Symptoms:
Not clickable button and not clickable PDF preview image. Console error: app.js?id=bd697d72bb94dfc380f8:8470 jQuery.Deferred exception: Cannot read properties of undefined (reading 'options') TypeError: Cannot read properties of undefined (reading 'options') at new FLIPBOOK.Main (versteckter Link) at t.fn.flipBook (versteckter Link) at HTMLDivElement. (versteckter Link) at Function.each (versteckter Link) at HTMLDocument. (versteckter Link) at mightThrow (versteckter Link) at process (versteckter Link) undefined jQuery.Deferred.exceptionHook @ app.js?id=bd697d72bb94dfc380f8:8470 process @ app.js?id=bd697d72bb94dfc380f8:8258 setTimeout (async) (anonymous) @ app.js?id=bd697d72bb94dfc380f8:8292 fire @ app.js?id=bd697d72bb94dfc380f8:7920 fireWith @ app.js?id=bd697d72bb94dfc380f8:8050 fire @ app.js?id=bd697d72bb94dfc380f8:8058 fire @ app.js?id=bd697d72bb94dfc380f8:7920 fireWith @ app.js?id=bd697d72bb94dfc380f8:8050 ready @ app.js?id=bd697d72bb94dfc380f8:8530 completed @ app.js?id=bd697d72bb94dfc380f8:8540 app.js?id=bd697d72bb94dfc380f8:8479 Uncaught TypeError: Cannot read properties of undefined (reading 'options') at new FLIPBOOK.Main (flipbook.min.js?ver=4.6.5:1:11064) at t.fn.flipBook (flipbook.min.js?ver=4.6.5:1:103) at HTMLDivElement. (embed.js?ver=4.6.5:1:4607) at Function.each (app.js?id=bd697d72bb94dfc380f8:4805:19) at HTMLDocument. (embed.js?ver=4.6.5:1:85) at mightThrow (app.js?id=bd697d72bb94dfc380f8:8186:29) at process (app.js?id=bd697d72bb94dfc380f8:8254:12)

Questions:
Why does the Real3D Flipbook & PDF Viewer plugin stop working when WPML is activated?
Is there a known compatibility issue between WPML and the Real3D Flipbook & PDF Viewer plugin?
How can I resolve the console error related to 'Cannot read properties of undefined (reading 'options')'?