...
generating gallery for gallery/images_contours_and_fields... [ 38%] image_demo.py
generating gallery for gallery/images_contours_and_fields... [ 40%] image_masked.py
generating gallery for gallery/images_contours_and_fields... [ 42%] image_nonuniform.py
generating gallery for gallery/images_contours_and_fields... [ 45%] image_transparency_blend.py

Exception occurred:
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 530, in _make_image
    np.asarray(alpha_channel, np.float32) * out_alpha * alpha,
ValueError: operands could not be broadcast together with shapes (370,370) (100,100)
The full traceback has been saved in /tmp/sphinx-err-glmke_9_.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!

# Sphinx version: 1.8.5
# Python version: 3.8.2 (CPython)
# Docutils version: 0.16 release
# Jinja2 version: 2.10.1
# Last messages:

# Loaded extensions:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/sphinx/cmd/build.py", line 300, in build_main
    app = Sphinx(args.sourcedir, args.confdir, args.outputdir,
  File "/usr/lib/python3/dist-packages/sphinx/application.py", line 263, in __init__
    self._init_builder()
  File "/usr/lib/python3/dist-packages/sphinx/application.py", line 325, in _init_builder
    self.emit('builder-inited')
  File "/usr/lib/python3/dist-packages/sphinx/application.py", line 510, in emit
    return self.events.emit(event, self, *args)
  File "/usr/lib/python3/dist-packages/sphinx/events.py", line 80, in emit
    results.append(callback(*args))
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_gallery.py", line 283, in generate_gallery_rst
    generate_dir_rst(src_dir, target_dir, gallery_conf,
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_rst.py", line 327, in generate_dir_rst
    intro, cost = generate_file_rst(
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_rst.py", line 740, in generate_file_rst
    output_blocks, time_elapsed = execute_script(script_blocks,
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_rst.py", line 659, in execute_script
    output_blocks = [execute_code_block(compiler, block,
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_rst.py", line 659, in <listcomp>
    output_blocks = [execute_code_block(compiler, block,
  File "/usr/lib/python3/dist-packages/sphinx_gallery/gen_rst.py", line 565, in execute_code_block
    images_rst = save_figures(block, script_vars, gallery_conf)
  File "/usr/lib/python3/dist-packages/sphinx_gallery/scrapers.py", line 236, in save_figures
    rst = scraper(block, block_vars, gallery_conf)
  File "/usr/lib/python3/dist-packages/sphinx_gallery/scrapers.py", line 99, in matplotlib_scraper
    fig.savefig(image_path, **these_kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/figure.py", line 2180, in savefig
    self.canvas.print_figure(fname, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/backend_bases.py", line 2082, in print_figure
    result = print_method(
  File "/usr/lib/python3/dist-packages/matplotlib/backends/backend_agg.py", line 527, in print_png
    FigureCanvasAgg.draw(self)
  File "/usr/lib/python3/dist-packages/matplotlib/backends/backend_agg.py", line 388, in draw
    self.figure.draw(self.renderer)
  File "/usr/lib/python3/dist-packages/matplotlib/artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/figure.py", line 1708, in draw
    mimage._draw_list_compositing_images(
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 135, in _draw_list_compositing_images
    a.draw(renderer)
  File "/usr/lib/python3/dist-packages/matplotlib/artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/axes/_base.py", line 2647, in draw
    mimage._draw_list_compositing_images(renderer, self, artists)
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 135, in _draw_list_compositing_images
    a.draw(renderer)
  File "/usr/lib/python3/dist-packages/matplotlib/artist.py", line 38, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 618, in draw
    im, l, b, trans = self.make_image(
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 879, in make_image
    return self._make_image(
  File "/usr/lib/python3/dist-packages/matplotlib/image.py", line 530, in _make_image
    np.asarray(alpha_channel, np.float32) * out_alpha * alpha,
ValueError: operands could not be broadcast together with shapes (370,370) (100,100)