Issue 1:
Bug report

Bug summary

It crashes on Mac Osx.

Code for reproduction

from matplotlib import pyplot as plt
plt.figure()

Actual outcome

2019-03-07 11:14:39.220 python[13951:2853154] -[QNSApplication _setup:]: unrecognized selector sent to instance 0x7fc9418afd10
2019-03-07 11:14:39.222 python[13951:2853154] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[QNSApplication _setup:]: unrecognized selector sent to instance 0x7fc9418afd10'
*** First throw call stack:

Expected outcome

Matplotlib version

Operating system: OSX 10.13.6

Matplotlib version: 3.0.3

Matplotlib backend (TkAgg):

Python version: 3.6.5

Jupyter version (if applicable):

Other libraries:

I installed Matplotlib by pip

Issue 2:
Bug report

Bug summary

plt.plot() fails with error

libc++abi.dylib: terminating with uncaught exception of type NSException

Code for reproduction

from matplotlib import pyplot as plt

plt.plot()

Actual outcome

2019-02-11 22:09:09.936 python[17037:389239] -[NSApplication _setup:]: unrecognized selector sent to instance 0x7fab105e6460
2019-02-11 22:09:09.937 python[17037:389239] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSApplication _setup:]: unrecognized selector sent to instance 0x7fab105e6460'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff43503ded __exceptionPreprocess + 256
1 libobjc.A.dylib 0x00007fff6f5cf720 objc_exception_throw + 48
2 CoreFoundation 0x00007fff43581195 -[NSObject(NSObject) __retain_OA] + 0
3 CoreFoundation 0x00007fff434a5a60 ___forwarding___ + 1486
4 CoreFoundation 0x00007fff434a5408 _CF_forwarding_prep_0 + 120
5 libtk8.6.dylib 0x0000000122c6531d TkpInit + 413
6 libtk8.6.dylib 0x0000000122bbd17e Initialize + 2622
7 _tkinter.cpython-37m-darwin.so 0x00000001229e5a0f _tkinter_create + 1183
8 python 0x000000010eb5a8b6 _PyMethodDef_RawFastCallKeywords + 230
9 python 0x000000010ec9ab47 call_function + 247
10 python 0x000000010ec98684 _PyEval_EvalFrameDefault + 45284
11 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
12 python 0x000000010eb59577 _PyFunction_FastCallDict + 231
13 python 0x000000010ebdd0b1 slot_tp_init + 193
14 python 0x000000010ebe7091 type_call + 241
15 python 0x000000010eb5a283 _PyObject_FastCallKeywords + 179
16 python 0x000000010ec9abe4 call_function + 404
17 python 0x000000010ec98778 _PyEval_EvalFrameDefault + 45528
18 python 0x000000010eb5a078 function_code_fastcall + 120
19 python 0x000000010ec9aafe call_function + 174
20 python 0x000000010ec98684 _PyEval_EvalFrameDefault + 45284
21 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
22 python 0x000000010eb59577 _PyFunction_FastCallDict + 231
23 python 0x000000010eb5d4a2 method_call + 130
24 python 0x000000010eb5aef2 PyObject_Call + 130
25 python 0x000000010ec988cf _PyEval_EvalFrameDefault + 45871
26 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
27 python 0x000000010eb5a783 _PyFunction_FastCallKeywords + 195
28 python 0x000000010ec9aafe call_function + 174
29 python 0x000000010ec986bf _PyEval_EvalFrameDefault + 45343
30 python 0x000000010eb5a078 function_code_fastcall + 120
31 python 0x000000010ec9aafe call_function + 174
32 python 0x000000010ec986bf _PyEval_EvalFrameDefault + 45343
33 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
34 python 0x000000010eb5a783 _PyFunction_FastCallKeywords + 195
35 python 0x000000010ec9aafe call_function + 174
36 python 0x000000010ec986bf _PyEval_EvalFrameDefault + 45343
37 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
38 python 0x000000010eb5a783 _PyFunction_FastCallKeywords + 195
39 python 0x000000010ec9aafe call_function + 174
40 python 0x000000010ec98684 _PyEval_EvalFrameDefault + 45284
41 python 0x000000010ec8c2d2 _PyEval_EvalCodeWithName + 418
42 python 0x000000010ecf0c40 PyRun_FileExFlags + 256
43 python 0x000000010ecf00b7 PyRun_SimpleFileExFlags + 391
44 python 0x000000010ed1c7ec pymain_main + 9564
45 python 0x000000010eb2ca9d main + 125
46 libdyld.dylib 0x00007fff7069ded9 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

Matplotlib version

Operating system: macOS 10.14.3 (Mojave)

Matplotlib version: 3.0.2

Matplotlib backend (print(matplotlib.get_backend())): TkAgg

Python version: 3.7.1

miniconda installed using the bash script (version 4.6.3).

Python environment created with conda:

conda create -n py37 python=3.7
conda activate py37

matrplotlib installed using conda

conda install matplotlib

The same error is obtained in the base environment (matrplotlib installed in the same way). Everything installed from a fresh miniconda installation, using the default channel.

I've seen a bunch of open/closed similar issues, but none seem to solve the problem.