Pre-compute the fallbacks on FontFallbackIter::new

src/font/system.rs

@@ -116,9 +116,6 @@ pub struct FontSystem {
 
     /// List of fallbacks
     pub(crate) fallbacks: Box<dyn Fallback>,
-
-    /// Scratch buffer for fallback list
-    pub(crate) scratch_fallbacks: Vec<&'static str>,
 }
 
 impl fmt::Debug for FontSystem {
@@ -216,7 +213,6 @@ impl FontSystem {
             shape_run_cache: crate::ShapeRunCache::default(),
             shape_buffer: ShapeBuffer::default(),
             fallbacks: Box::new(fallbacks),
-            scratch_fallbacks: Vec::new(),
         }
     }