Give sidebar a z-index

[nbdd0121]

This ensures that sidebar does not overlap with content when horizontal scrollbar is present.

The overlap is visible in https://docs.rs/ndarray/0.15.3/ndarray/struct.ArrayBase.html.

Discovered by @m13253.

[rust-highfive]

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez

[rust-highfive]

r? @CraftSpider

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[nbdd0121]

The error doesn't seem relevant...

[GuillaumeGomez]

I don't think this is the right fix. The content shouldn't be larger that the container. The scrollbar should be on the <table> directly.

[nbdd0121]

The scrollbar should be on the <table> directly.

Many elements could cause the overflow, not just a table. E.g. a very long inline code block could cause the content to overflow too, but you cannot put a scrollbar on it because it isn't and shouldn't be display: block.

For this particular case a scrollbar on the table might be desirable, but in general style still shouldn't break when content overflows.

[GuillaumeGomez]

Agreed. I'm planning to wrap the <table> items into <div> and to add this CSS rule:

.docblock * {
    max-width: 100%;
    overflow-x: scroll;
}

That should prevent most issues.

[nbdd0121]

Should be overflow-x: auto;

[GuillaumeGomez]

I opened #88742 so I think this PR can be closed. To give a few more information about why I don't think this is a good idea: hiding the issue (but making the scrolled content go under the sidebar) doesn't fix the original problem. Instead of making the whole doc block scroll, I prefer to limit it to the element having a too big width directly.

Thanks in any case for bringing this issue to our attention! :)

[nbdd0121]

No I think both PRs should be merged. They tackle different problems:

• Fix table in docblocks #88742 reduces the chance of overflow happening;
• This PR addresses the behaviour when overflow happens: even if overflow happens, the result should still be sane.

As I said earlier, it not feasible in general to prevent overflow from happening at all. Have

`<insert a very long symbol name here>` Note that's an inline code block so it doesn't make sense to put a scroll bar on it.

in the doc still shouldn't break the style and cause the overlap to happen.

[nbdd0121]

Oh I miss the .docblock > * { max-width: 100%; } part. I suppose that'll work too.