We currently support two URL formats

1) absolute
   must start with http: or https:

2) controller/action
   like a labkey url without the path, the path of the current container will be filled in
   e.g. /project/begin.view

It seems we have a problem that needs to be fixed as far as length. But for now, one way to shorten the URL is to use the container id or container rowid instead of the path in the url e.g.

https://www.labkey.org/project/79704b7a-b9ab-e733-0002-0106c1fdd116/begin.view
or
https://www.labkey.org/project/__r2/begin.view?

There are two ways to figure out this shorter link. The easiest is to click the "Permanent Link" in the navigation area on the left. The other is to go to admin/<path>/containerId.view e.g. https://www.labkey.org/admin/home/containerId.view to see the containerId and rowid.

Matt