- The `GODOT_SERVER` preprocessor define is no longer available in Godot 4, since the dedicated server platform was removed.
- Replaced a reference to `GODOT_HTML5` with `GODOT_WEB` since that platform was also renamed in Godot 4.
- Remove note about `<DefineConstants>` that only really applies to Godot 3.
- The `TOOLS` define wasn't documented anywhere.
- Add `GODOT_REAL_T_IS_DOUBLE` define to the list.
- Custom features as defines were removed and are no longer added.
- `_Process` and `_PhysicsProcess` take their delta argument as a `double`
- Use string interpolation instead of concatenating strings
- Use `string` instead of `String` (`using System` was removed from everywhere in a previous PR)
- Use `System.Array.Empty<T>()` to init empty arrays
- Use `SignalName.*` instead of `nameof(*)` for signals
- Do not use `event` as an argument name (that's a keyword)
- Match node paths to screenshots when retrieving nodes from the tree
- Add a C# example for scene unique nodes
- Update the "Cross language scripting" page
- Add a note about using `is` against `null`
- Removed typographic marks in the entire repo
- Removed a line about why we don't use a wiki
- Indented notes with 4 spaces
- Addressed review comments
