1) Create a new actor based blueprint
2) open the event graph and add a comment node
3) attempt to type in a long comment to either the node title or the right click context comment field.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-36788 in the post.
| 0 | 
| Component | UE - Gameplay - Blueprint | 
|---|---|
| Affects Versions | 4.14 | 
| Target Fix | 4.16 | 
| Fix Commit | 3359445 | 
|---|---|
| Main Commit | 3380073 | 
| Created | Oct 4, 2016 | 
|---|---|
| Resolved | Mar 22, 2017 | 
| Updated | Apr 5, 2017 | 
| 2989 - projectgheist |