{@html html-string} replacing tr,td tags

[mishrasatyam]

If a table's tbody has an existing tr element and we place another tr before it using @html tag,
the tags tr, td are stripped.
To Reproduce
Please see here:
https://svelte.dev/repl/dee930a465e14a31baa1846003463e12?version=3.22.3

Thanks

[Conduitry]

It looks like this happened between 3.6.11 and 3.7.0 as a result of #3329. I'm not sure what can reasonably be done about this. The newer way of handling {@html} blocks involves creating a temporary <div> and setting its innerHTML, which presents a problem here, as certain types of elements are not allowed as children of <div>s.

[GrygrFlzr]

What if instead of creating a <div>, the compiler creates a <template> element instead?
It seems like it was meant for element fragments.

[GrygrFlzr]

In the meantime, here's a workaround which uses <template>:
https://svelte.dev/repl/bf25404232fe427899450cc397f461a6?version=3.22.3

[Rich-Harris]

As an alternative to using <template> (which has the IE compatibility issue @Conduitry identifies in #4857), what if we used the same element as the parent, or maybe only in cases where these issues arise?

e.g.

-html_tag = new HtmlTag(/*html_data*/ ctx[0], null);
+html_tag = new HtmlTag(/*html_data*/ ctx[0], null, 'tbody');

That would require the compiler to know the parent element type at runtime, which precludes top-level {@html ...} tags and any future <svelte:element> additions. Though perhaps it could be done at runtime instead, if we rejiggered things in HtmlTag slightly.

[Rich-Harris]

FYI have implemented the proposed alternative in #4863

[Conduitry]

This is fixed in 3.23.0 - https://svelte.dev/repl/dee930a465e14a31baa1846003463e12?version=3.23.0