Allow pass-through of output

src/IOCapture.jl

@@ -105,7 +105,15 @@ function capture(f; rethrow::Type=Any, color::Bool=false)
     # pipe to `output` in order to avoid the buffer filling up and stalling write() calls in
     # user code.
     output = IOBuffer()
-    buffer_redirect_task = @async write(output, pipe)
+    bufsize = 128
+    buffer_redirect_task = @async begin
+        while true
+            buffer = read(pipe, bufsize)
+            write(output, buffer)
+            write(default_stdout, buffer)
+            isempty(buffer) && break
+        end
+    end
 
     if old_rng !== nothing
         copy!(Random.default_rng(), old_rng)