On Tuesday we will roll out a change to Franklin that eliminates the much-unloved iframe in which availability information displays. The March 2019 Alma release corrects a bug that prevented us from releasing this feature in August 2018 as originally planned.
The window you see here:

will be replaced by a new interface element that contains the same information, but in a way that doesn’t trigger security warnings in some users’ browsers:

We are not planning a user-facing announcement of this because to users it should appear to be a cosmetic improvement. The Discovery Team has done extensive testing, but if you notice issues, please contact the Help Desk as usual.