Remove popover content with .children().detach() instead of .empty() so it can be reused
Use .end() to remove extra line
Fix #14411 by setting JSON Content-Type for Gist API request
grunt
Assume Element.getBoundingClientRect() exists; Fixes #14093

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Merge pull request #14244 from programcsharp/master

Remove popover content with .children().detach() instead of .empty()