René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"New configure_subplots behaves badly on TkAgg backend","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n**Bug summary**\r\n\r\nAfter #16818, with the TkAgg backend, configure subplots window can't be closed and the sliders do not respond to input. The window close issue is straightforward to understand: the button response calls `Gcf.destroy` but the figure is intentionally not registered, so the `FigureManagerTk.destory` is never called. I suspect (but have not confirmed) that the slider events are being lost due to the new figure manager making a new `tkinter.Tk` instance [here](https://github.com/anntzer/matplotlib/blob/c55ca9fd64f74c4bb9ad57ea371ae8a1ec07b7d0/lib/matplotlib/backends/_backend_tk.py#L849). [EDIT: NOPE, see comment]\r\n\r\nCC @anntzer \r\n\r\n**Code for reproduction**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug.\r\nPlease make sure to minimize the number of dependencies required, and provide\r\nany necessary plotted data.\r\nAvoid using threads, as Matplotlib is (explicitly) not thread-safe.--\u003e\r\n\r\n```python\r\nimport matplotlib\r\nimport matplotlib.pyplot as plt\r\n\r\nmatplotlib.use(\"TkAgg\")\r\nplt.plot([1,2,3],[1,2,5])\r\n#  if not interactive\r\nplt.show()\r\n# click Configure Subplots\r\n```\r\n\r\n**Actual outcome**\r\n\r\ninteractive Tk window but sliders don't work and close window button is not responsive\r\n\r\n**Expected outcome**\r\n\r\nprevious behavior\r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: Win10\r\n  * Matplotlib version: master\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): TkAgg\r\n  * Python version: 3.8.5\r\n  * Jupyter version (if applicable):\r\n  * Other libraries: \r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/richardsheridan","@type":"Person","name":"richardsheridan"},"datePublished":"2020-08-19T13:40:23.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/18299/matplotlib/issues/18299"}