How to add Thumbnail to an own Discord Notification

Found the script below on the net, unfortunately I can’t find the URL to assign the credits to the creator.
I added the script to my Tautulli notification agent for Discord. But what I’m still missing is a larger image that is displayed on the right. With the Tautulli default settings, I only manage to display a poster or thumbnail below the text.

Maybe someone has an idea how I can get a poster or something similar on the right side. Thank you!

As u can see in the image, adding {poster_thumb}, also {thumb} just outputs parts of the Link. And having the Poster underneath just looks ugly.

>>> Subject :arrow_right: **({server_name}) | ({library_name})** | Library updated! 

<movie>{timestamp} - {datestamp}
**A new film has been added.**

:clapper:  **Title:** *{title} ({year}) - {content_rating}*
:office:  **Studio:** *{studio}*
:construction_worker_tone1:  **Directors:** *{directors}*
:couple:  **Actors:** *{actors:[1:5]}*
:clock4:  **Movie length:** *{duration} minutes*
:performing_arts:  **Genres:** *{genres}*
:gear:  **Video resolution:** *{video_width}x{video_height} - {video_resolution}p  ({file_size})*
:link:  **Link to IMDB:** {imdb_url}
:link:  **Link to TMDb:** {themoviedb_url}
:link:  **Link to Plex library:** [Plex Web]({plex_url})
**★ {rating} | ** *{summary}*