I don't know what this is used for but is there any action we should be taking to treat this prior to March 2019? Will it affect anything at all? This appears to be used in out of the box code out of our control.
There is a response in this thread from MeghanAtkins explaining that this message relates to the use of Live UI which we consider essential - and that you are looking to fix it in a 8.1 patch.
We are currently using 8.1.4 please could you advise which patch version does / will include a fix for this problem as this may inform our upgrade strategy?
Unfortunately we wouldn't easily be able to backport the fix to a previous Pega release as it was a pretty risky refactor and there would be a large testing effort required to do that. I spoke to the engineer who worked on the fix and he mentioned that when the API gets deprecated that Live UI should hopefully still function ok as the code itself is in a try/catch block.
Hopefully moving to 8.3 is a feasible option though since we can't fully guarantee the feature would work.