René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Doc]: alpha setting for annotation `TextArea`","articleBody":"### Bug summary\n\nI've been adding annotations following the excellent examples at [AnnotationBbox demo](https://matplotlib.org/stable/gallery/text_labels_and_annotations/demo_annotation_box.html#sphx-glr-gallery-text-labels-and-annotations-demo-annotation-box-py), but I'd like to make the text box transparent.  From the [TextArea docs](https://matplotlib.org/stable/api/offsetbox_api.html#matplotlib.offsetbox.TextArea.set) it looks like `my_text_area.set(alpha=x)` should work, but it doesn't seem to have any effect.\r\n\r\nPerhaps there is another way to set this that I have missed?\n\n### Code for reproduction\n\n```python\nimport matplotlib.pyplot as plt\r\nfrom matplotlib.offsetbox import TextArea, AnnotationBbox\r\n\r\nimport numpy as np\r\n\r\nrng = np.random.default_rng()\r\n\r\ndata = rng.normal(size=30)\r\n\r\nplt.rcdefaults()\r\n\r\n_ , ax = plt.subplots()\r\nax.hist(data)\r\n\r\noffsetbox = TextArea('Look over there!')\r\noffsetbox.set(alpha=0.3)\r\n\r\nab = AnnotationBbox(offsetbox, (0.8, 0.8),\r\n            xybox=(0, 1),\r\n            xycoords='axes fraction',\r\n            boxcoords='data',\r\n            arrowprops=dict(arrowstyle=\"-\u003e\"))\r\n\r\nax.add_artist(ab)\r\n\r\nplt.show()\n```\n\n\n### Actual outcome\n\n![mpl_annotation_box_alpha](https://user-images.githubusercontent.com/10599679/200327684-8719ff0a-93b1-4f13-90df-aa365105eb55.png)\r\n\n\n### Expected outcome\n\nThe text box should be transparent.\n\n### Additional information\n\nI tried a few versions back to 3.3, but the result was the same.\n\n### Operating system\n\nRHEL7\n\n### Matplotlib Version\n\n3.6.2\n\n### Matplotlib Backend\n\nQtAgg\n\n### Python version\n\n3.8.13\n\n### Jupyter version\n\nN/A\n\n### Installation\n\nconda","author":{"url":"https://github.com/rcomer","@type":"Person","name":"rcomer"},"datePublished":"2022-11-07T14:15:31.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/24390/matplotlib/issues/24390"}