Files
Shane 344a43feca feat(infinite-scroll): adding preserveRerenderScrollPosition property (#30566)
Issue number: resolves internal

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

Currently, if you use infinite scroll and fully change out elements in
the DOM, you'll lose your scroll position. This can present as a race
condition in some frameworks, like React, but will present pretty
consistently in vanilla JavaScript. This happens because the browser is
removing the old elements from the DOM and adding the new ones, and
during that time the container holding the old elements will shrink and
the browser will adjust the top position to be the maximum of the new
container height.

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

With this new property (`preserveRerenderScrollPosition`) set, we will
loop through siblings of the infinite scroll and set their min-heights
to be their current heights before triggering the `ionInfinite` event,
then we clean up after complete is called by restoring their previous
min-heights or setting them to auto if there were none. This prevents
the container from resizing and the browser from losing the scroll
position.

## Does this introduce a breaking change?

- [ ] Yes
- [X] No

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## Other information

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screenshots of how the component looks before and after the change. -->

**Current dev build**: 
```
8.6.6-dev.11753719591.13a5c65f
```
2025-07-30 10:23:00 -07:00
..