Merge pull request #10059 from minrk/rebase-9885

re-issue ipympl PR

IPython/core/pylabtools.py

@@ -23,7 +23,9 b" backends = {'tk': 'TkAgg',"
             'nbagg': 'nbAgg',
             'notebook': 'nbAgg',
             'agg': 'agg',
-            'inline' : 'module://ipykernel.pylab.backend_inline'}
+            'inline': 'module://ipykernel.pylab.backend_inline',
+            'ipympl': 'module://ipympl.backend_nbagg',
+}
 
 # We also need a reverse backends2guis mapping that will properly choose which
 # GUI support to activate based on the desired matplotlib backend.  For the
@@ -221,8 +223,8 b' def select_figure_formats(shell, formats, **kwargs):'
     formats = set(formats)
 
     [ f.pop(Figure, None) for f in shell.display_formatter.formatters.values() ]
-
-    if matplotlib.get_backend().lower() == 'nbagg':
+    mplbackend = matplotlib.get_backend().lower()
+    if mplbackend == 'nbagg' or mplbackend == 'module://ipympl.backend_nbagg':
         formatter = shell.display_formatter.ipython_display_formatter
         formatter.for_type(Figure, _reshow_nbagg_figure)