Fix thin strokes on macOS

Remove the `font.use_thin_strokes` config, which only did anything on
macOS and only prior to Big Sur. Instead, we will enable or disable
"font smoothing" on macOS based on the `AppleFontSmoothing` user
default.

These changes let users get the "thin strokes" behavior by setting
`AppleFontSmoothing` to 0 with:

```sh
$ defaults write -g AppleFontSmoothing -int 0
```

(Or replace `-g` with `org.alacritty` to apply this setting only to
Alacritty.app, rather than the whole system.)

Add a `removed` config attribute to show helpful warnings to users
who are using config options that don't do anything anymore, and apply
this attribute to `font.use_thin_strokes`.

Bump `crossfont` to 0.5.0 to pick up the new font smoothing behavior.
This release also includes a fix for a crash when trying to load a
disabled font.

Fixes #4616.
Fixes #6108.

1 files changed, 1 insertions, 5 deletions

diff --git a/alacritty/src/display/mod.rs b/alacritty/src/display/mod.rs
index f1f51ec7..79e57307 100644
--- a/alacritty/src/display/mod.rs
+++ b/alacritty/src/display/mod.rs
@@ -411,7 +411,7 @@ impl Display {
         // Guess the target window dimensions.
         debug!("Loading \"{}\" font", &config.font.normal().family);
         let font = &config.font;
-        let rasterizer = Rasterizer::new(estimated_scale_factor as f32, font.use_thin_strokes)?;
+        let rasterizer = Rasterizer::new(estimated_scale_factor as f32)?;
         let mut glyph_cache = GlyphCache::new(rasterizer, font)?;
         let metrics = glyph_cache.font_metrics();
         let (cell_width, cell_height) = compute_cell_size(config, &metrics);
@@ -488,10 +488,6 @@ impl Display {
         let background_color = config.colors.primary.background;
         renderer.clear(background_color, config.window_opacity());
 
-        // Set subpixel anti-aliasing.
-        #[cfg(target_os = "macos")]
-        crossfont::set_font_smoothing(config.font.use_thin_strokes);
-
         // Disable shadows for transparent windows on macOS.
         #[cfg(target_os = "macos")]
         window.set_has_shadow(config.window_opacity() >= 1.0);