I've been testing the safeAreaBar modifier to develop a custom tab bar. From my understanding, this should enable the .scrollEdgeEffectStyle to work with this bar, but I don't see any effect.
Could you please clarify the difference between safeAreaBar and safeAreaInset?
You are correct in saying that the safeAreaBar modifier additionally adjusts the scroll edge effect. However, I believe that this modifier is currently broken (as of beta 2), because its behaviour seems to be no different to using safeAreaInset. I have filed feedback for this: FB18350439.
There’s a known issue with safeAreaBar on the beta builds and the engineering team is investigating it.
Please open a bug report and post the FB number here once you do. Bug Reporting: How and Why? has tips on creating your bug report.