Broken links to other resources - how do you keep them up to date?

Document links can be easily mass-changed when they are part of an element in the Dictionary, after for example a library migration.

But what if they are in the other attributes (like the Document links attribute) in Tasks or Diagrams? Or what if just a single document is moved on the external resource?

How do you keep your links to external documents from not breaking or how can you quickly detect and correct these?

We encourage people to not include version numbers in their documents which they refer to on a Sharepoint for example, but use a proper revision sheet instead. This prevents a category of broken links, but not all.

Any tips and tricks? Or would a link checker in Signavio be helpful?

Thanks in advance for your insights,