Flickering when combining transitions and animate:flip on Safari

Why this is a good first issue

Browser-specific rendering issue requiring Safari-specific fixes without clear solution path.

AI Summary

The issue involves flickering animations when combining transitions with animate:flip specifically in Safari, with a provided reproduction case. The fix likely requires understanding Svelte's animation system and Safari's rendering quirks, but the exact solution isn't immediately obvious from the report.

Issue Description

Describe the bug

Updating a state during transition causes flickering when combining animate:flip with a transition in Safari, doesn't happen on chrome. Kinda similar to #17215 , except this affects only Safari and isn't fixed in the latest version.

Reproduction

https://svelte.dev/playground/9e21f02c5afa45ae84adb8b8d0b76c5b?version=5.46.1 Only on safari, you might have to refresh a few times

Logs

System Info

System:
    OS: macOS 26.2
    CPU: (14) arm64 Apple M4 Pro
    Memory: 226.41 MB / 24.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 25.2.1 - /opt/homebrew/bin/node
    npm: 11.6.2 - /opt/homebrew/bin/npm
    pnpm: 10.26.1 - /opt/homebrew/bin/pnpm
    Deno: 2.6.4 - /Users/****/.deno/bin/deno
  Browsers:
    Safari: 26.2
Chromium
  npmPackages:
    svelte: ^5.46.1 => 5.46.1

Severity

blocking an upgrade