Tippyjs: createSingleton does not use correct function content in 6.0

[sqal]

Bug description

Hi. There's some regression in createSingleton method when tippy's content prop is a function. Please open [email protected] reproduction link and take a look at the console logs. You can see that content function is called 4 times but it should be called 3 times (3 tippy instances). Fourth call receives some ghost div element which isn't even in the DOM which makes the content set to an empty string.

Reproduction

[email protected] - https://jsfiddle.net/uh9aftcm/
[email protected] - https://jsfiddle.net/pmwfn41h/

[KubaJastrz]

Callstack is leading to these:

https://github.com/atomiks/tippyjs/blob/bbbd40c61ea3c701841e6b14c682780a2db927c4/src/addons/createSingleton.ts#L66

https://github.com/atomiks/tippyjs/blob/bbbd40c61ea3c701841e6b14c682780a2db927c4/src/createTippy.ts#L124

https://github.com/atomiks/tippyjs/blob/bbbd40c61ea3c701841e6b14c682780a2db927c4/src/template.ts#L92

https://github.com/atomiks/tippyjs/blob/bbbd40c61ea3c701841e6b14c682780a2db927c4/src/template.ts#L38-L57

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It seems like the issue is caused by the fact that the addons call tippy separately with their own div() element.

In v5 it worked fine because even though new popper was being created, setContent helper didn't reevaluate content prop if it was provided as a function (like in your fiddle).

https://github.com/atomiks/tippyjs/blob/f2e51ed3386dc1ed7582e216cf623f3cefec751c/src/createTippy.ts#L105

https://github.com/atomiks/tippyjs/blob/f2e51ed3386dc1ed7582e216cf623f3cefec751c/src/popper.ts#L65-L78

[KubaJastrz]

And the bug itself is caused by createSingleton's onTrigger hook that receives wrong instance (the 4th one, created on empty div with no content) and overrides content prop on all previous instances.

Never mind, I got it wrong. It seems like the reference element used to evaluate computedContent is the one that is created for purposes of singleton instance.