diff --git a/src/terminal/Parser.zig b/src/terminal/Parser.zig
index 88e7edf7c..34e7e30f4 100644
--- a/src/terminal/Parser.zig
+++ b/src/terminal/Parser.zig
@@ -166,12 +166,18 @@ pub const Action = union(enum) {
                         // of invisible characters we don't want to handle right
                         // now.
 
-                        // All others do the default behavior
+                        // All others do the default behavior. Note the max
+                        // depth of 1: this is only used for logging so we
+                        // only want the top-level fields. Larger depths
+                        // instantiate a recursive formatter for every nested
+                        // type of every action payload (e.g. the full
+                        // osc.Command union), which costs tens of kilobytes
+                        // of binary size.
                         else => try writer.printValue(
                             "any",
                             .{},
                             @field(self, u_field.name),
-                            3,
+                            1,
                         ),
                     }
                 }
@@ -386,10 +392,7 @@ inline fn doAction(self: *Parser, action: TransitionAction, c: u8) ?Action {
             // We only allow colon or mixed separators for the 'm' command.
             if (c != 'm' and self.params_sep.count() > 0) {
                 @branchHint(.cold);
-                log.warn(
-                    "CSI colon or mixed separators only allowed for 'm' command, got: {f}",
-                    .{result},
-                );
+                warnCsiSepMismatch(result.csi_dispatch);
                 break :csi_dispatch null;
             }
 
@@ -406,6 +409,20 @@ inline fn doAction(self: *Parser, action: TransitionAction, c: u8) ?Action {
     };
 }
 
+/// Log a warning for a CSI dispatch with colon/mixed separators on a
+/// non-'m' command.
+///
+/// This is noinline on purpose so that this unlikely (cold) behavior
+/// doesn't bloat the hot dispatch path which has been measured to actually
+/// affect both binary size and performance due to icache busts.
+noinline fn warnCsiSepMismatch(csi: Action.CSI) void {
+    @branchHint(.cold);
+    log.warn(
+        "CSI colon or mixed separators only allowed for 'm' command, got: {f}",
+        .{csi},
+    );
+}
+
 pub inline fn clear(self: *Parser) void {
     self.intermediates_idx = 0;
     self.params_idx = 0;