In #21569, revising What's New for 2.7, Nick is planning to add the following:

+PEP 434: IDLE Enhancement Exception for All Branches
+----------------------------------------------------
+
+:pep:`434` describes a general exemption for changes made to the IDLE
+development environment shipped along with Python. This exemption makes it
+possible for the IDLE developers to provide a more consistent user
+experience across all supported versions of Python 2 and 3.
+
+For details of any IDLE changes, refer to the NEWS file for the specific
+release.

I think the same should be added to What's New 3.4+ so Idle users are warned and informed that there might be otherwise unexpected changes. At minimum, the last phrase should be changed to "refer to the successive Idle sections of the changelog", where changelog' is linked as it is at the top of the file.

I am not sure where to put this. The 3.4 What's New has no Idle section. I did not think to write one :-(. Of course, there was almost nothing new since the previous 3.3.x bugfix release. I guess such a section should be a cumulative summary what was added since the previous x.y.0 release, even if all went into one of the bugfix releases, including the pending final maintenance release.

#21961 ends with the entry I added for 3.4 and 3.5.  3.7 (and checking 3.6) will be a new issue.