No text and links in breadcrumbs

I have a big problem with this plugin.

When it show the dropbox folder inserted in a page, the breadcrumbs appear broken, it only show the “>” icon and the name of the folder has gone.

In a complex site with multisite, and multiple plugins, the links doesn’t appear neither.

The big issue with that is that I can’t navigate trough the different folders. If I enter to a child folder, I can’t access to the parent.

I have tested in different versions of wordpress (4.9.5, 4.9.6 and 4.9.7) and always have the same problem.

In this images you can see the problem:

Simple install:
https://colillas.com/images/galeria-Dropbox-SIMPLE-INSTALL.png.

Complex install:
https://colillas.com/images/galeria-Dropbox-COMPLEX-INSTALL.png.