Hi,
I'm able to reproduce the issue. For some reason there Youtube tag is not being rendered. Please raise a support ticket for this via Acyba's website (https://www.acyba.com/contact-us.html) and include a link to this thread.
Note for Acyba:
<span
style='font-size:12.0pt;font-family:"Segoe UI",sans-serif;color:black'><a
href="https://vimeo.com/388340785" target="_blank"><span
style='font-family:"Helvetica",sans-serif;color:#2199E8;text-decoration:
none;text-underline:none'><img border=0 id="_x0000_i1025"
src="https://i.vimeocdn.com/filter/overlay?src=http%3A%2F%2Fi.vimeocdn.com%2Fvideo%2F851564710_640.jpg&src=http%3A%2F%2Ff.vimeocdn.com%2Fp%2Fimages%2Fcrawler_play.png"
style='outline: 0;-ms-interpolation-mode: bicubic;max-width:100%;
border-bottom-style:none;border-left-style:none;border-right-style:
none;border-top-style:none;clear:both;display:block;padding-bottom:
0in;padding-left:0in;padding-right:0in;padding-top:0in;text-decoration:
none;width:auto' class=donotresize></span></a> - this works</span></span><span
style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'><o:p></o:p></span></p>
</span>
<p class=MsoNormal style='word-break:break-word'
data-mce-style="font-family: Helvetica; font-size: 16px; font-weight: normal; font-style: normal; color: #000000; word-break: break-word;"><span
style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'> <o:p></o:p></span></p>
<p class=MsoNormal style='word-break:break-word'
data-mce-style="font-family: Helvetica; font-size: 16px; font-weight: normal; font-style: normal; color: #000000; word-break: break-word;"><span
style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'> <o:p></o:p></span></p>
<p class=MsoNormal style='margin-bottom:12.0pt;box-sizing: border-box;
word-break:break-word'
data-mce-style="box-sizing: border-box; margin-bottom: 1em; color: #000000; font-family: Helvetica; font-size: 16px; font-weight: normal; font-style: normal; word-break: break-word;"><span
style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'>-
this does not work<o:p></o:p></span></p>