Cannot upload an image for new answer

As a logged user on my anspress instance I´m able to upload a picture through the modal window for a question BUT if I try to do it the same way also for an answer I got this error:

<# if (typeof content !== undefined) { #>{{title}}<#} #>
<# if (typeof content !== undefined) { #>{{content}}<#} #>
<# if (typeof content !== undefined) { #>{{_.each(buttons, function(btn) { #>AP="{{BTN.CB}}" APQUERY="{{BTN.QUERY}}"<#} #>>{{BTN.LABEL}} <# }); #><# } #>

Catched on WordPress 5.1.1 + Anspress 4.1.15 + Askbug 3.1.9
Steps to reproduce:

1. Post a question as a logged user (upload images is allowed without any problems)
2. Post an answer right after that and try to upload an image
3. Notification error as you can see higher is present and nothing else happened -> so user cannot upload an image for his answer