Debug performance difference in VS vs Editor

Godot Version

4.3.1

Question

If I run my C# Godot code via Visual Studio debugger in Debug mode - it runs at 120fps+
If I run the exact same code via the Godot Editor - it runs at 25fps

Surely it’s debug and goes via the debugger either way?

Why the difference?

It caused me to scratch my head a fair bit today as I was trying to debug performance and seeing a massive change when using the debugger to the editor/etc.

Just curious.