René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Regression: Setting alpha on legend handle changes patch color","articleBody":"### Bug summary\n\nBug #11702 seems to have reappeared: calling set_alpha on a legend handle causes the color of the patch in the legend to change in a filled area plot.\n\n### Code for reproduction\n\n```python\nimport matplotlib.pyplot as plt\r\nimport pandas as pd\r\n\r\ndf = pd.DataFrame({\r\n    'sales': [3, 2, 3],\r\n    'visits': [20, 42, 28],\r\n    'day': [1, 2, 3],\r\n})\r\n\r\ndf.plot.area(x='day')\r\nlegend = plt.legend()\r\nfor p in legend.get_patches():\r\n    p.set_alpha(1)\n```\n\n\n### Actual outcome\n\n![2021-12-15T173908](https://user-images.githubusercontent.com/1017726/146228281-75cf9850-27c2-4fca-b32a-8c21114199c8.png)\r\n\n\n### Expected outcome\n\nThe patch for 'visits' should be orange.\n\n### Additional information\n\nThis was working fine at least until mpl 3.3.4.\r\n\r\nAs for the previous workaround, calling set_facecolor(get_facecolor()) before calling set_alpha() works. I'm using legend.get_patches() here instead of iterating through the handles directly, but there's no difference.\n\n### Operating system\n\nLinux (debian unstable)\n\n### Matplotlib Version\n\n3.5.0\n\n### Matplotlib Backend\n\nQt5Agg or agg\n\n### Python version\n\n3.9.9\n\n### Jupyter version\n\nn/a\n\n### Installation\n\nLinux package manager","author":{"url":"https://github.com/wavexx","@type":"Person","name":"wavexx"},"datePublished":"2021-12-15T16:49:21.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/21966/matplotlib/issues/21966"}