René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Implement `hoveron: 'fills'` for scattergl and scatterpolargl","articleBody":"During a [discussion in the plotly.py forums](https://community.plot.ly/t/windrose-chart-customization/12294/6) in came up that the hoverlabel for the `scatterpolar` trace has a different behavior when the `fill` state is set to `toself` than when it's set to `none`.\r\n\r\nCodePen: https://codepen.io/anon/pen/EpOGdX\r\n\r\n`fill: 'none'` for `scatterpolar`\r\n![screen shot 2018-08-09 at 5 52 32 am](https://user-images.githubusercontent.com/15064365/43891927-91b48ca0-9b98-11e8-8f5c-eae8ef370d64.png)\r\n\r\n`fill: 'toself'` for `scatterpolar`\r\n![screen shot 2018-08-09 at 5 52 59 am](https://user-images.githubusercontent.com/15064365/43891938-9d875670-9b98-11e8-9388-26264a00c9fa.png)\r\n\r\nIt also seems that the `hoverinfo` propery has no effect when `fill` is `toself`.\r\n\r\nI did the same comparison with the `scatterpolargl` trace and it has the behavior that I expected:\r\n\r\n`fill: 'toself;` for `scatterpolargl`\r\n![screen shot 2018-08-09 at 5 56 18 am](https://user-images.githubusercontent.com/15064365/43892066-f6761244-9b98-11e8-9817-8a2a199025dc.png)\r\n\r\nI don't know if this is a bug in `scatterpolar` or `scatterpolargl`, but I find the current `scatterpolargl` behavior (The behavior consistent with `fill` of `none`) to be more helpful.\r\n\r\n","author":{"url":"https://github.com/jonmmease","@type":"Person","name":"jonmmease"},"datePublished":"2018-08-09T10:00:27.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":10},"url":"https://github.com/2887/plotly.js/issues/2887"}