diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
index 70389be97e39..c1fde0dcb023 100644
--- a/lib/matplotlib/pyplot.py
+++ b/lib/matplotlib/pyplot.py
@@ -232,10 +232,26 @@ def switch_backend(newbackend):
close("all")
if newbackend is rcsetup._auto_backend_sentinel:
+ current_framework = cbook._get_running_interactive_framework()
+ mapping = {'qt5': 'qt5agg',
+ 'qt4': 'qt4agg',
+ 'gtk3': 'gtk3agg',
+ 'wx': 'wxagg',
+ 'tk': 'tkagg',
+ 'macosx': 'macosx',
+ 'headless': 'agg'}
+
+ best_guess = mapping.get(current_framework, None)
+ if best_guess is not None:
+ candidates = [best_guess]
+ else:
+ candidates = []
+ candidates += ["macosx", "qt5agg", "gtk3agg", "tkagg", "wxagg"]
+
# Don't try to fallback on the cairo-based backends as they each have
# an additional dependency (pycairo) over the agg-based backend, and
# are of worse quality.
- for candidate in ["macosx", "qt5agg", "gtk3agg", "tkagg", "wxagg"]:
+ for candidate in candidates:
try:
switch_backend(candidate)
except ImportError:
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index fe5885e0ac9c..4494efa35437 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -228,3 +228,37 @@ def test_never_update(monkeypatch, capsys):
# test framework doesn't see tkinter callback exceptions normally
# see tkinter.Misc.report_callback_exception
assert "Exception in Tkinter callback" not in capsys.readouterr().err
+
+
+@pytest.mark.skipif(sys.platform != "linux", reason="this a linux-only test")
+@pytest.mark.backend('Qt5Agg', skip_on_importerror=True)
+def test_lazy_linux_headless():
+ test_script = """
+import os
+import sys
+
+# make it look headless
+del os.environ['DISPLAY']
+
+# we should fast-track to Agg
+import matplotlib.pyplot as plt
+plt.get_backend() == 'agg'
+assert 'PyQt5' not in sys.modules
+
+# make sure we really have pyqt installed
+import PyQt5
+assert 'PyQt5' in sys.modules
+
+# try to switch and make sure we fail with ImportError
+try:
+ plt.switch_backend('qt5agg')
+except ImportError:
+ ...
+else:
+ sys.exit(1)
+
+"""
+ proc = subprocess.run([sys.executable, "-c", test_script])
+ if proc.returncode:
+ pytest.fail("The subprocess returned with non-zero exit status "
+ f"{proc.returncode}.")
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