WPForo Advanced Attachments GPL 

wpForo Advanced Attachments addon is a full-fledged file uploading, attaching, displaying, and managing solution for wpForo. It comes with super interactive, multi-functional file attachment features. Allows you to attach multiple files, images, videos, audio, and all other file types you’ve allowed in settings.

Files can be inserted inline, between post-content texts. It opens a nice lightbox slider with many features to view and watch different types of attached files. This addon keeps user-specific attachments in a separate media library and allows users to use the same file on different topics and posts. You can limit file types, max uploaded file size, and do a quick translation of front-end phrases using addon settings.