When I create a link to a file on the filesystem, I usually copy the address line from the Windows Explorer for instance c:\temp\somefile.pdf. I prepend file:/// to create an URL. Unfortunately, Confluence deletes the single backslash when displaying the link. It leaves file:///c:tempsomefile.pdf which doesn't work.

I do not want to replace \ with
or / for every external file or directory I want to link to. It should work without any special treatment.

Proposal: Add a "local file" link type to the Add Link popup. Then Confluence can handle the link and convert it to handle backspaces correctly. Backspaces work fine with all browsers on Windows, so they can be rendered in HTML like they were entered.