When a Texture Sample's MipValue is set to something other than "none" (which adds the extra pin), attempting to convert that Texture Sample to a parameter will cause the Editor to crash.
(Simple repro steps below)
*Included link from licensee for reference
1. Create a material
2. Add a Texture Sample
3. Set MipValue to "Mip Level" or "Mip Bias"
4. Right click and Convert to Parameter
5. Editor Crashes
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-16181 in the post.