Support conditionally rendered tooltip content

[hmnd]

For Tooltip content that needs to be loaded async, I prefer wrapping the content in {#if open} and enabling forceVisible. The way the next-gen Tooltip works makes this no longer possible, as it now depends on an HTML element being bound to tooltip.content before the content can be shown.

[hmnd]

This is also a big problem on pages with a large number of tooltips. The content positions remain continuously updated by floating ui while not displayed, resulting in low performance and lag.

[TGlide]

This is also a big problem on pages with a large number of tooltips. The content positions remain continuously updated by floating ui while not displayed, resulting in low performance and lag.

Please open a separate issue, with reproduction