### Description SS5 replaced `$First` and `$Last` with `$IsFirst` and `$IsLast`, but this change wasn’t reflected in elemental ### Additional context or points of discussion _No response_ ### Validations - [X] You intend to implement the feature yourself - [X] You have read the [contributing guide](https://docs.silverstripe.org/en/contributing/code/) - [X] You strongly believe this feature should be in core, rather than being its own community module - [X] You have checked for existing issues or pull requests related to this feature (and didn't find any) ## PRs - https://github.com/silverstripe/silverstripe-elemental/pull/1275 - https://github.com/silverstripe/developer-docs/pull/631