Conflicts with mybb forum

[NelsonGaldeman]

I've added a bitcoin donation button (Hosted on my own servers), but if the button it's enabled I can't even create a thread, when I send it it shows the thread text as "undefined" (and many other issues) it's strage, but after I deleted coinwidget code, the forum started working as usual. Not sure what could cause this.

Here is the forum: https://amxmodx-es.com

If you go to: https://amxmodx-es.com/index.php?widget=true it will show the donation button. It doesn't look like broken, but it actually is.