Comments and Attachments UX

I'm trying to find examples of sites which have the ability to make a comment and add multiple attachments to said comment. So far, the only example I have found of this is teamgantt.com which is kind of what I'm looking for. Does anyone have any other examples of sites that do this or have any ideas about it? Specifically, I'm looking for what might happen when there are a number of attachments - is there a scroll function or something else? - and whether or not there should be thumbnail images of the attachments. Thanks.