[Shell / Shell Panel] When `content-behind` is set, Shell Panel in slot "panel-bottom" can position incorrectly

[macandcheese]

Check existing issues

• [x] I have checked for existing issues to avoid duplicates

Actual Behavior

When Shell has content-behind set, a Shell Panel of in slot "panel-bottom" with displayMode="float" will not display properly if there is not content slotted in "panel-top".

Expected Behavior

I'd expect the slotted "panel-bottom" content to always position in the bottom, without the need to populate "panel-top".

Reproduction Sample

https://codepen.io/mac_and_cheese/pen/bGzjMLg?editors=1100

Reproduction Steps

1. Open Codepen
2. See incorrectly positioned "bottom panel"
3. Uncomment collapsed "top panel"
4. See positioning is correct

Reproduction Version

1.10

Relevant Info

There are some inconsistencies with how this behaves when content-behind is set, or unset.

Regression?

No response

Priority impact

p3 - want for upcoming milestone

Impact

No response

Calcite package

• [x] @esri/calcite-components
• [ ] @esri/calcite-components-angular
• [ ] @esri/calcite-components-react
• [ ] @esri/calcite-design-tokens
• [ ] @esri/eslint-plugin-calcite-components

Esri team

Calcite (design)

[macandcheese]

The workaround is to have a collapsed Shell Panel, in the panel-top slot.