Web Edit/Open in . . .

You can edit Office files, text files, markdown files (.md), HTML files, and log files without downloading them from FileCloud. Office file types open in Office Online, Collabera CODE, or OnlyOffice depending on which application you have installed and which application your admin has configured for Web Edit in FileCloud. The other file types open in FileCloud's built-in editors.

To perform a Web Edit, hover over the file and click the  icon.
For an Office file type, the icon or menu option reflects the external editor available for the file with Web Edit. For non-Office file types, the icon or menu option appears as Edit Online. Clicking opens the file in FileCloud's built-in editor.

(For both Office and non-Office files, if the Edit in Desktop feature is enabled, you also see the Open in Desktop option, which downloads the file and opens it in its native application, then automatically uploads it to FileCloud when you save it.)

If Web edit or Desktop edit is not available for a file type, the icon appears disabled. 

Video: Editing a text file

Video: Editing in Office Online