Hi, 

To reproduce:

1) Open a new topic in this forum

2) Paste a medium / large image from the CLIPBOARD in the text body.

3) If the image is large enough, when clicking "New topic" to post the topic, ithc,io would throw an exception: body: expected text between 1 and 20480 characters.

I thinks this is because the image is read as characters, so the body message surplus the 20480 character limit. In that case, that wouldn't be a bug, but the error give you no clue that you cannot upload because the image is too big.

Example: (The following image hve been posted using the conventional method: Add image, uplaod image, etc ): 

OS: linux 20.04.

Web browser: Brave.