Re: [csswg-drafts] [css-overflow-3][css-overflow-4][css-box-3] A switch for bottom/right (end) overflow to not be scrollable contribution, like top/left (start) (#3953)

> OK, so the first case would be solved if we made clip disable scrolling in that axis in the cases where it otherwise behaves like hidden, yeah?

Yep, this would solve for how currently the spec would require a non-semantic `clip` wrapper around content inside the scroll container.

> As for the second, I'm having trouble following what you're trying to do. Maybe a simplified testcase would help?

Negative margins allow for some interesting scroll effects with position sticky, but though a negative bottom margin may create a shorter content box for the immediate sticky elements parent, it does not pass that "shorter content edge" up to the scroll container, with the scroll container expanding its scrollable overflow to contain the sticky element. So...

```html
<scrollport>
  <box>
    <content></content>
    <sticky style="margin-bottom: -100px"></sticky>
  </box>
</scrollport>
```
In this example, the `<box>` would be made 100px shorter than the sticky elements bottom edge, though of course the scrollports scrollHeight would not be cut short the 100px, unlike what rightly happens in the top/left edge of a scroll container.

I also wonder what this means for scrollable overflow regarding alignment/logical specs for scroll content aligning/starting on the bottom/right flowing upward/leftward?

And again, won't `overflow:clip` computing to `overflow:hidden` on the root scroller keep from paint optimizations, especially for things like a menu transformed way up out of view inside a root that is intended to absolutely never have scrollable overflow or scroll?

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Received on Thursday, 23 May 2019 22:22:22 UTC