It doesn't make sense to do the same behaviour like what we did on Easysocial, if that is video link like youtube or vimeo , you should use the build-in Youtube block or Vimeo block on the composer (screenshot :
http://take.ms/r6xZz ), but based on what i know, so far only you request this to support indavideo.hu video.

I believe my colleague already explained to you in your previous thread, if you have report that issue to this indavideo.hu video provider developer, once they fix this, I think we can add a new feature in Easyblog which can support this indavideo.hu video in build-in composer.

By the way, if you would like to show that video on your blog, you can switch that Editor to use "Tiny-MCE" editor, then check my attached screenshot below how to insert the video on the blog.