.src file not found in %appdata%\Mp3tag\data\sources

The instruction for installing new Web Source scripts (.src files) is to place them in %appdata%\Mp3tag\data\sources.

With my installation they are not displayed in Mp3tag unless they are placed in %programfiles(x86)%\Mp3tag\data\sources. (%programfiles(x86)% is the default Mp3tag installation directory)

%appdata%\Mp3tag\data\sources seems to be ignored.

Why does this happen, contrary to the documentation?
Will there be a problem when updating or re-installing?