Previously, you could link to a file attached to the same Confluence page by:
- typing "["
- typing the start of the attachment name
- selecting the filename from the list, which would then be displayed as a text link.
In the recent editing updates (which are currently applied to new pages only) this does not seem to be possible.
In the new editor typing "/" gives you a list of the available actions, but there does not seem to be the option to link to an attached file, and have the link displayed as text.