- `@available` should not be used with other conditions (not sure if it breaks anything but it does trigger warnings in xcode)
- missing runtime check before using `modalInPresentation`, kept the precompiler instruction so it still builds on older xcodes.
This change fixes the problem when header would update to the previous screen configuration as a result of starting swipe back gesture but never restore to the original one in case swipe back gets cancelled (e.g. user didn't swipe far enough). The problem was that as a result of swipe back we'd apply header config changes but after cancel there was no trigger to reset header to the previous state.
