Merge pull request #2945 from rosteen/auto-backport-of-pr-2944-on-v3.…

…10.x

Backport PR #2944 on branch v3.10.x (fix: make standalone work with matplotlib >= 3.9.0)

standalone/jdaviz-cli-entrypoint.py

@@ -1,4 +1,11 @@
 import sys
+# this avoids:
+# ValueError: Key backend: 'module://matplotlib_inline.backend_inline' is not a valid value for backend; supported values are [...]
+# Although not 100% why, it has two effects:
+#  1. PyInstaller picks it up as a module to include
+#  2. It registers the backend, maybe earlier than it would be otherwise
+import matplotlib_inline
+import matplotlib_inline.backend_inline
 
 def start_as_kernel():
     # similar to https://github.com/astrofrog/voila-qt-app/blob/master/voila_demo.py